How did British politics reach this point?

Starmer, a softly spoken former human rights lawyer, had been hailed as a pragmatic and serious leader who could restore stability after years of political chaos and infighting that resulted in two changes of prime minister by the rightwing Conservative party after the 2019 general election.

But although he was elected with the biggest parliamentary majority in 100 years, there was a sense even among Labour supporters that Starmer lacked political nous and conviction. This was underlined by missteps including cutting some winter fuel subsidies for pensioners and a U-turn on welfare in the face of a parliamentary rebellion last year.

Starmer’s judgment was called into serious question after his decision to appoint a controversial former Labour minister, Peter Mandelson, as Britain’s ambassador to the US despite the latter’s known links to the child sex offender and financier Jeffrey Epstein.

After the true extent of Mandelson’s ties to Epstein became known in September 2025, Starmer sacked him – but it was too late to prevent the prime minister and his government from becoming embroiled in one of the worst political scandals since the second world war.

All the while, and amid deep unpopularity among voters, panic has continued to grow in Labour ranks that he has been unable to meet the challenge from Reform UK, the anti-immigration party headed by the divisive Farage.

Farage’s party routed Labour and the Conservatives in municipal elections last year and again last month, which was a catalyst for the draining away of support for Starmer and resignations by ministers in his government.

Both they and others who stayed in Starmer’s cabinet had privately and publicly urged him to resign, with backers of Burnham advocating for an orderly transition of power rather than a damaging leadership contest.

Who is Andy Burnham and how has he become the prime minister in waiting?

A veteran of the Labour governments of Brown and Tony Blair, 56-year-old Burnham has served since 2017 as the mayor of Greater Manchester, a newly created role which he was elected to after two failed bids to become Labour leader, in 2010 and 2015.

He has thrived in the position, earning the nickname “the King in the North” for his high-profile interventions in the distinctive politics of north-west England and for presiding over an economic boom in UK’s fastest-growing city region.

Burnham has long been regarded by many in Labour, including those on the moderate left, as the answer to the party’s woes and in particular to the draining away of its support in traditional working-class strongholds.

In January he was blocked by allies of Starmer from returning to parliament when a vacant Westminster seat in the Manchester area became available. But they could not prevent him from becoming the Labour candidate in a fresh special election this month in the north-west of England, after the local MP stood down.

His victory in the constituency of Makerfield has paved the way for his return to the Westminster parliament, where he is eligible to become the Labour leader and consequently prime minister.

However, it was the manner of Burnham’s win that underlined his credentials as the answer to the conundrum faced by Labour after its support collapsed in two previous special elections for vacant seats in Westminster. Not only did he did see off the Reform UK candidate last week, but he did so by a significant margin, resurrecting his party’s support in an area where the populists had made sweeping gains during local elections in May.

What happens next?

Starmer had already informed King Charles III of his intention to resign, as is required by convention, before he announced the news to the British public on Monday morning.

During his resignation speech, the Labour leader said he would ask his party’s ruling national executive committee to set out a timetable for a contest to replace him, with 9 July the date from which contenders can seek nominations by their fellow Labour MPs.

A process of hustings, where candidates would make their case to fellow Labour MPs, would be intended to be completed by 16 July, the last day before the UK parliament breaks up for its summer recess.

If more than one person reaches the nominations threshold, there would be a contest. That would take place when parliament is not sitting, among an electorate comprising hundreds of thousands of members of the Labour party and trade unions and affiliated bodies. Starmer would stay in post in the interim, with a new leader in place by the resupmtion of parliament on 1 September.

However, a contest is almost certain to be avoided after Wes Streeting, another influential Labour MP who resigned last month as England’s health secretary, made a U-turn on his previously declared intention to stand and announced he would back Burnham.

Should Burnham remain unchallenged, he is expected to become the Labour leader on 17 or 18 July. He would expect to receive a call from the king inviting him to form a government.

It is possible that another minister could enter the fray, and some Labour MPs believe a contest would help to challenge Burnham on his ideas and plans, but many others believe a so-called coronation would minimise the disruption and sense of chaos before the instalment of the UK’s seventh prime minister in 10 years.

Of the opposition party leaders, only Farage has called for a general election, claiming it is “ridiculous to pretend that Andy Burnham has any kind of meaningful mandate to lead the country”.

How would Andy Burnham govern?

Much has been made of Burnham’s record as mayor of the Greater Manchester area. Supporters point to the region’s growth as evidence of his competence and ability to meld social democratic ideas with business-friendly policies.

However, others hoping to establish what he stands for in a big picture sense have variously pointed to his faith – Burnham would be the first practising Catholic to become the UK’s prime minister – and the ideas he and others have put forward in speeches and writings that have come to be known as “Manchesterism”.

The term loosely refers to an argument for increasing devolution of decision-making powers from London to Britain’s cities and regions, providing investment in those regions and a much more interventionist state.

In contrast with the more pragmatic faction which had gathered around and supported Starmer, Burnham is also more closely associated with the so-called soft left of the Labour party while opponents on Britain’s political right have seized on Burnham’s past comments that politicians should not be “in hock” to the bond markets.

However, he has come to be regarded as a someone who has sought to bridge the right-left divides within Labour, albeit with critics ridiculing apparent changes of position on questions such as reopening the debate about whether Britain should seek to rejoin the European Union after the Brexit referendum in 2016.

On one other hot-button political issue, Burnham’s team have signalled that he would back controversial changes to the immigration system that have been pioneered by Starmer’s government, in a blow to those in Labour who hoped to soften them.

What does it mean for the next UK general election?

The UK’s next general election must be called by August 2029, although the prime minister can choose to hold it at any point before this.

Farage’s Reform UK have topped the opinion polls since last year, having gained a small foothold in parliament at the last general election. The party has consistently been projected to win a majority when British voters next elect a government.

Burnham can now lay claim to the mantle of being Labour’s potential “Reform slayer” by pointing to the line he drew in the sand in last week’s vote in Makerfield.

But Labour cannot run him as their candidate in every constituency across the UK, where his party faces challenges and an unprecedented array of rivals who include not just the populist right.

They also include the Green party of England and Wales, which has been outflanking Labour on the left among liberals and British Muslim voters in urban areas, and pro-independence nationalist parties in Scotland and Wales.

Quite apart from his electoral challenge, Burnham must grapple with profound policy challenges.

They include pressure to find money to fund Britain’s military and a debate within the party about how the welfare system can be overhauled.

Above all though, there is the need to get Britain’s economy firing on all cylinders and equip the country to weather the storm clouds gathering in the wake of the war in the Gulf.