Emergency services aircraft such as air ambulances would be prioritised under 'worst case scenario' planning for jet fuel shortages, the Daily Mail can reveal today.
Ministers are currently war-gaming the possibility of supplies of the fuel starting to dry up around the May half-term holidays, in about five to six weeks' time, if the Strait of Hormuz remains closed.
As it stands, officials believe less than 10 per cent of flights would have to be cancelled if shortages hit because Britain has 'diversified' where it buys the fuel from.
However, this could still affect thousands of passengers as the summer holiday high season ramps up.
Officials have told airlines they must give passengers at least two weeks' notice of any cancellations to avoid a repeat of chaotic scenes during the Covid-19 pandemic, when flights were axed at the eleventh hour and passengers left in the lurch.
According to sources familiar with shortages planning, were supplies to completely dry up, emergency services craft such as air ambulances and lifeguard and police helicopters would be prioritised for receiving supplies.
However, it is understood that ministers believe this is an unlikely scenario.
It came as the head of a global energy watchdog said they believed shortages in Europe could be just six weeks away.
Workers use a fuel truck to service an easyJet plane at Milan's Malpensa Airport on Monday
Fatih Birol, the executive director of the International Energy Agency, said there would be flight cancellations 'soon' if oil supplies from the Middle East were not restored within the coming weeks.
Mr Birol said the conflict was causing 'the largest energy crisis we have ever faced'.
He said Asian counties such as Japan, India and China that rely on energy from the Middle East are on 'the front line', but pressure will then 'come to Europe and the Americas'. Europe has 'maybe six weeks or so (of) jet fuel left', he warned.
If the Strait of Hormuz is not reopened, the impact on Europe may be that 'some of the flights from city A to city B might be cancelled as a result of lack of jet fuel', he added.
How are global airlines responding to the surge in jet fuel prices?
AEGEAN AIRLINES: The Greek airline expects suspended Middle East flights and a spike in fuel prices to have a 'notable impact' on its next results.
AIRASIA X: The Malaysian airline's executives said the company had cut 10% of flights across the group, with a surcharge of about 20% on fuel.
AIR FRANCE-KLM: The airline group said it planned to increase long-haul ticket prices to address surging fuel costs, with cabin fares set to rise by €50 (£44) per round trip.
AIR INDIA: The Indian flag carrier said it would revise its fuel surcharge from a flat domestic surcharge to a distance-based grid, as surcharges on international routes don't compensate for an exponential rise in jet fuel prices.
AIR NEW ZEALAND: The airline said on April 7 it would slash flights through May and June and hike fares, having been one of the first to confirm broad price increases when the war began.
AKASA AIR: India's Akasa Air said it was introducing a fuel surcharge ranging between 199 and 1,300 Indian rupees (£2 to £10) on domestic and international flights.
ALASKA AIR: The US airline said it will hike fees for the first checked bag by $5 (£4) and by $10 (£7) for the second on its North American flights, as well as for its Hawaiian Airlines unit. It increased prices for a third checked bag from $50 (£37) to $200 (£148).
AMERICAN AIRLINES: The US carrier said it would hike checked baggage fees by $10 (£7) each for the first and second checked bags and by $150 (£111) for the third checked bag on domestic and short-haul international flights. The airline also trimmed certain benefits for economy passengers.
CATHAY PACIFIC: The Hong Kong airline said it would cut some flight from mid-May until the end of June, cancelling about 2% of its scheduled passenger flights, while its budget airline HK Express is cutting around 6% of flights. The carrier previously said it would hike its fuel surcharge by 34% across routes from April 1 and review them every two weeks.
CEBU AIR: The Philippines-based airline said the sharp rise in fuel prices was a concern and it would continue to review its pricing and network strategies to mitigate the impact.
CHINA EASTERN AIRLINES: The airline said it would raise fuel surcharges for domestic flights from April 5, with flights of 800km and below hit with a 60 yuan (£6) surcharge and a 120 yuan (£13) surcharge for flights over 800km.
DELTA AIR LINES: Delta said it would cut capacity by around 3.5 percentage points from its original plan and raise fees for checked bags in an attempt to offset soaring jet fuel costs, with an increase of $10 (£7) on the price of first and second checked bags and a $50 (£37) increase on the third checked bag. The US airline pulled all planned capacity growth for the current quarter and forecast profit below Wall Street expectations.
EASYJET: EasyJet CEO Kenton Jarvis said European consumers should expect higher ticket prices towards the end of summer, when existing fuel hedges come to an end.
FRONTIER AIRLINES: The US airline is reviewing its full-year forecast as fuel prices have increased significantly since it issued the outlook.
GREATER BAY AIRLINES: The Hong Kong-based company said it would raise fuel surcharges on most routes from April 1, while keeping them unchanged on mainland China and Japan routes. Its surcharge for flights between Hong Kong and the Philippines will more than double.
HONG KONG AIRLINES: The airline said it would raise fuel surcharges by up to 35% from March 12, with the sharpest increase on flights between Hong Kong and the Maldives, Bangladesh and Nepal, where charges would rise to HK$384 (£36) from HK$284 (£27).
IAG: British Airways-owner IAG said on March 10 it did not plan to increase ticket prices immediately, as it has hedged much of its fuel for the short- to medium-term.
INDIGO: India's biggest airline said it would introduce fuel charges on domestic and international flights from March 14, including a charge of 900 rupees (£7) for flights to the Middle East and a charge of 2,300 rupees (£18) for flights to Europe.
JETBLUE AIRWAYS: The US-based low-cost carrier said it was increasing fees for optional services such as checked baggage as it experiences 'rising operating costs'. Baggage prices will rise by either $4 (£3) or $9 (£7), it said.
KOREAN AIR: The South Korean flag carrier will enter emergency management mode from April, as rising oil prices weigh on costs, a source told Reuters. The airline plans to implement phased response measures based on oil price levels, and step up company-wide cost efficiency to offset surging fuel costs.
PAKISTAN INTERNATIONAL AIRLINES: The carrier said it would raise domestic flight fares by $20 (£15) and international fares by up to $100 (£74), citing higher fuel surcharges.
QANTAS AIRWAYS: Australia's Qantas said it had delayed a planned A$150million buyback and was raising its estimated fuel bill for the second half of 2026 to A$3.1bn-A$3.3bn, from a previous A$2.5bn forecast.
SAS: The Scandinavian airline said it would cancel 1,000 flights in April because of high oil and jet fuel prices, after cancelling a 'couple hundred' flights in March. SAS, which had already increased flight prices, said that even if it tried to absorb the rising fuel costs, the price surge would still be a blow to the aviation industry.
SPRING AIRLINES: The budget Chinese airline said it would raise fuel surcharges on domestic flights from April 5, with details to be announced later.
SOUTHWEST AIRLINES: The American carrier said it would hike checked baggage fees by $10 (£7) for the first and second bags, raising costs to $45 (£33) for the first bag and $55 (£41) for the second.
TAP: The Portuguese airline said its price hikes would partially mitigate the impact of fuel price changes on its revenue.
THAI AIRWAYS: The Thailand-based carrier said it would raise fares by 10% to 15% to address rising fuel costs.
TURKISH AIRLINES, LUFTHANSA: SunExpress, a joint venture between Turkish Airlines and Lufthansa, said it would impose a temporary fuel surcharge of €10 (£9) per passenger from May 1 on routes between Turkey and Europe. The surcharge will apply to bookings made on or after April 1 for departures on or after May 1.
T'WAY AIR: The South Korean low-cost carrier said on April 13 it plans to furlough some of its cabin crew without pay in May and June as part of its measures to address the impact of the war in the Middle East.
UNITED AIRLINES: The US airline is cutting unprofitable flights over the next two quarters as it prepares for oil prices to remain above $100 until the end of 2027, CEO Scott Kirby said. United has raised fares without materially hurting bookings in response to the rapid increase in oil and jet fuel prices, its Chief Commercial Officer said. The carrier is also increasing first and second checked bag fees by $10 (£7) for customers travelling in the US, Mexico and Canada and Latin America, it said.
VIETJET: The Vietnamese budget airline said it had adjusted flight frequency on selected routes due to potential fuel shortages.
VIETNAM AIRLINES: The carrier plans to cancel 23 flights per week across domestic routes from April, Vietnam's aviation authority said, after the airline requested government assistance to remove an environmental tax on jet fuel.
VIRGIN ATLANTIC: The airline is adding fuel surcharges to fares but will still struggle to return to profitability this year, its CEO Corneel Koster told the Financial Times.
VIRGIN AUSTRALIA: Virgin Australia said it expects an increase in jet fuel cost of around A$30million (£16million) to A$40million (£21million) for the second half of this fiscal year, as well as a 1 per cent reduction in capacity in the fourth quarter. The airline previously said it was adjusting fares to reflect rising cost pressures.
WESTJET: The Canadian airline will add a C$60 (£32) fuel surcharge to some bookings and combine flights as costs soar.
The US-Israel war on Iran has caused turmoil in global energy markets since the first strikes at the end of February.
In retaliation, Iran has effectively closed the strait, a vital export route for oil from the Gulf.
As a result, jet fuel prices have rocketed at a faster rate than petrol or diesel prices for cars at forecourts, roughly doubling since the start of the conflict.
It means holidaymakers are also facing sharp fare increases this summer, with some airlines already passing on higher fuel costs to passengers.
EasyJet said today that the conflict in the Middle East cost the airline about £25million in higher jet fuel prices last month.
It means the airline will likely hike fares to cover the loss, with several others facing a similar situation.
EasyJet chief executive Kenton Jarvis said: 'We only ever in this industry have three to four weeks visibility (of jet fuel supplies), and that is the same as it was pre-crisis.
'We have visibility to the middle of May, and we have no concerns. What we're seeing is airports and fuel suppliers working well to bring jet fuel to the airports.'
The Luton-based airline said it expects to report a headline loss before tax of between £540million and £560million for the six months to the end of March.
The war has introduced 'near-term uncertainty around fuel costs and customer demand', easyJet reported.
Bookings are down two percentage points for the three months to the end of both June and September compared with a year ago.
A government spokesperson said: 'We continue to engage with British airlines to support their operations against the backdrop of war in the Middle East, and to limit the impact on passengers.
'Most airlines purchase their aviation fuel in advance to offset price fluctuations, however we are aware of the impact to businesses, and are working with international allies to see a reopening of the Strait as soon as possible.'
Meanwhile Spain and Portugal are bracing for a tourism boom as millions of travellers avoid war-affected destinations in the Middle East.
Summer flight bookings to Spain have soared 32 per cent year-on-year with hotel searches up 28 per cent, according to digital travel marketing platform Sojern.
Portugal has recorded a 21 per cent rise in flight bookings with hotel searches rising 16 per cent, as both countries see a surge in interest for late spring and summer.
Travel data firm Mabrian reported a notable shift where tourists are no longer booking Middle Eastern destinations and instead heading for the southern Mediterranean.
Countries in the eastern Mediterranean such as Cyprus, where a drone hit a UK base last month, have faced a wave of cancellations - with demand also falling for the likes of Turkey, Greece and Egypt.
European officials are drafting up emergency plans to tackle the jet fuel crisis after airlines warned of possible shortages within weeks due to the Iran war.
The war has sent jet fuel prices soaring as much as $200 (£158) a barrel in recent weeks, upending the aviation industry and forcing airlines to curb growth plans.
The latest average global jet fuel cost was $198 per barrel last week - double the $99 in late February when the war began, the International Air Transport Association said.
Meanwhile families with young children have been stranded abroad due to the new Entry/Exit System (EES) which requires travellers from third-party countries, including the UK, to have their fingerprints and photos taken as they enter the Schengen area.
Further checks take place when they leave, and because these can take hours, some travellers have been stuck at passport control after their flights have already left.
Passengers travelling across Europe were hit by delays and cancellations over the weekend with long queues forming at destinations including Geneva, Lisbon and Malta – while others faced two-hour waits on Monday in Brussels and Amsterdam.
Despite concerns over the EES, Spanish tourism industry group Exceltur has noted an uplift in bookings to the country due to the conflict, with vice president Oscar Perelli saying today: 'Summer holidays are planned months in advance.
'As destinations that attract large numbers of tourists are affected by the conflict, a significant part of this safe-haven effect is already materialising in purchases and bookings to Spain.'
Sylvia Weiler, Sojern's general manager for global destinations, added: 'Travellers are adapting rather than retreating.'
Up to 181million tourists visit the Middle East and eastern Mediterranean annually. Spain alone received a record 97million last year.
Exceltur last week forecast Spain's tourism activity would grow 2.5 per cent in real terms this year to €227billion (£197billion) up from a previous 2.4 per cent projection and last year's 2.1 per cent expansion.
It estimates diverted tourists could generate an additional €4.2billion (£3.7billion) to that industry total this year.
The sector, a cornerstone of the economy that has helped Spain outpace most European peers in the past few years, is expected to expand faster than overall economic growth, which is forecast at 2.3 per cent.
Spain's main hotel association Cehat expects room occupancy rates to rise by up to 3 per cent this summer.
'Tourists are choosing destinations farther from Mediterranean conflict zones, such as the Canary Islands, for their summer family holidays,' said Cehat president Jorge Marichal, warning however that gains could be offset by a reduction in overall travel.
Airlines are boosting capacity, with nearly 6 per cent more seats available in April than a year ago, according to the official tourism agency Turespaña, with the strongest increases on flights from Britain and the US.
However, higher jet fuel prices and further disruptions for long-haul travelers at Middle Eastern transit hubs could curtail the gains, Exceltur cautioned.
Mr Marichal added: 'It will all depend on what happens in the Strait of Hormuz, because all these forecasts could go out the window.'
Now, the European Union has been writing up plans to tackle the looming jet fuel supply crunch and maximise refinery output ahead of the busy summer seasons..
Europe is more dependent on jet fuel imports than for any other transport fuel, with some 75 per cent from the Middle East – and the European Commission will introduce EU-wide mapping of refining capacity for oil products from next month.
The EU is also working on measures targeting jet fuel supply, but those are believed to still be in development – with the full plans due to be published next Wednesday.
Hopes are rising of a swift end to the conflict after President Donald Trump said the war could end soon - telling the world to watch out for an 'amazing two days'.
But airlines are preparing for a potential supply crunch, with the International Energy Agency (IEA) forecasting jet fuel shortages by June if the region can only replace half of the supplies it normally gets from the Middle East.
Increased imports from Africa and the US are unlikely to fully make up for the drop, while fuel handling consortia that feed into airports do not always keep long-term stocks – and many airports do not keep large stocks on hand, according to analysts.
Some airports have warned of shortages within three weeks if the Strait of Hormuz remains closed to fuel shipments.
As domestic oil production has shrunk and governments have sought to shift to cleaner energy sources, Europe's refining capacity has declined in recent years.
The IEA said this month that many European refiners are already operating at maximum capacity for jet fuel production.
A spokesperson for Heathrow Airport said that the impacts of the war had not yet hit its operations, although it was monitoring the situation.
The proposed EU rules would not be expected to impact Britain, which is outside the 27-member bloc.
Jet fuel supplies are highly uneven across Europe. Spain has eight refineries and is a net exporter of jet fuel, while imports cover more than 60 per cent of British demand.
Fatih Birol, the executive director of the International Energy Agency, speaks to the Associated Press today as he claims jet fuel shortages in Europe could be just six weeks away
European airlines have asked the EU to improve monitoring of jet fuel supplies and consider joint purchasing of kerosene.
The OECD Europe region, which includes EU countries as well as others like Britain and Norway, imports more than 30 per cent of its jet fuel, IEA data shows, with most going through the Strait.
The EU requires its members to maintain 90 days of emergency oil reserves as a buffer against supply shocks. This does not include a specific requirement on jet fuel, although countries can count it and other oil products towards their stock.
The Mediterranean 'leisure airports' used by millions of holidaymakers heading to Spain, Greece and Italy could be hit especially hard by the jet fuel issues as they operate on 'thin fuel buffers' - meaning they are not set up to store large reserves.
The airport industry association ACI Europe has warned they are about three weeks away from 'systemic' jet fuel shortages if the Strait is not fully reopened by the end of April.
Even Mr Trump succeeds in 'permanently' opening the Strait as he said he would yesterday, safety concerns could remain, including fears of widespread undersea mines.
Airports in Asia are also vulnerable due to their reliance on supplies from the Gulf.
EasyJet today forecast a headline pre-tax loss of £540million to £560million for the first half, including £25million in additional fuel costs in March and £30 pounds in expenses from higher legal provisions. It reported a loss of £394million a year earlier.
The airline added that summer bookings were down on last year, with third-quarter bookings 63 per cent sold compared with 65 per cent last year. Fourth-quarter bookings were 30 per cent sold so far.
EasyJet had already warned that the Iran war would push up ticket prices towards the end of the summer, and that the conflict had impacted bookings, with customers moving away from booking trips to Turkey, Egypt and Cyprus.
Carsten Spohr, the chief executive of Lufthansa, one of Europe's biggest airlines, has already warned of planes being grounded due to a lack of fuel.
Passengers left behind at Milan Linate Airport on Sunday due to the border control chaos
The rollout of the EU's new Entry/Exit System causes delays at Brussels Airport on Monday
These new biometric Entry/Exit System machines have been set up at Malaga Airport in Spain
He added: 'Kerosene will remain in short supply and therefore more expensive for the rest of the year.'
Virgin Atlantic has already placed an extra £50 fuel surcharge on economy tickets, with premium economy and business class fares increasing by £180 and £360 respectively.
Chief executive Corneel Koster warned that passengers will face further increased prices for the next few months and possibly the rest of the year.
The UK is dependent on jet fuel from the Middle East, with Kuwait supplying four million tons annually.
Experts at flight comparison booking website Skyscanner urged customers to 'shop around and compare live prices' given dynamic pricing strategies used by airlines.
The company's travel expert Laura Lindsay told the Daily Mail: 'Prices are not rising on every route, nor at the same rate, which means there are still deals to be found for travellers who can be flexible or are open to exploring alternative destinations.'
Speaking about potential delays caused by the EES rollout, she added: 'Europe remains a key summer destination, but travellers should plan ahead and allow extra time. There is a possibility of longer wait times at some border crossing points, particularly during busy holiday periods.
'That does not mean disruption everywhere, but it does mean some travellers may face additional border processing time in certain locations.
'Travellers should check the latest travel advice, allow extra time, make sure the relevant documents are ready before departure, and monitor airport and airline communications closely.'