Poland's prime minister has questioned America's loyalty to NATO in the event that the continent is attacked by Russia. 

Donald Tusk said that the question of the US' role in the Western alliance needed to be answered soon as Russia could attack an alliance member in a matter of 'months.' 

He told the FT that Europe's 'biggest, most important question is if the United States is ready to be as loyal as it is described in our [NATO] treaties.'

Tusk's comments are a rare direct rebuke of US president Donald Trump's flip-flopping on his position on NATO. 

From warning that he would pull the US out of NATO entirely to exploring ways to punish the alliance for not doing enough to help his war in the Middle East, members of the defence bloc have been left confused as to what Trump wants. 

He claimed to have 'no complexes' about relations between Poland and the US, adding: 'Washington treats Poland as the best and the closest ally in Europe.'

But, he insisted: 'For me, the real problem is what it is in practice if something happens.

'I want to believe that [Article 5] is still valid, but sometimes, of course, I have some problems. 

'I don’t want to be so pessimistic . . . but what we need today is also practical context.' 

He pointed to NATO's milquetoast reaction to the Russian incursion of drones into Poland last year, which saw the Kremlin send around 20 drones violate Polish airspace. 

Few of Poland's NATO allies saw it as a material attack, with the alliance reluctantly scrambling fighter jets to shoot some of the drones down. 

Tusk recalled: 'I had some problems during the night in September when we had this pretty massive drone provocation made by the Russians 

'It wasn’t easy for me to convince our partners in Nato that it wasn’t a random incident, it was a well-planned and prepared provocation against Poland. 

'For some of our colleagues, it was much easier to pretend that nothing happened. This is why I want to be certain that if something happened, that... Russia knows the reaction will be tough and unequivocal.' 

He added that NATO also had to rise up to face the challenge Russia poses itself: 'For the whole eastern flank, my neighbours . . . the question is if NATO is still an organisation ready, politically and also logistically, to react, for example against Russia if they try to attack.'

Tusk's warning comes just as the Pentagon was revealed to be exploring ways for the US to punish NATO countries for failing to support the Iran war, including reviewing the UK's claim to the Falklands Islands and suspending Spain from the alliance.  

The policy options are detailed in an email expressing frustration at some allies' perceived reluctance or refusal to grant Washington access, basing and overflight (ABO) rights for the Iran war, a US official told Reuters.

The email stated that ABO is 'just the absolute baseline for NATO,' according to the official, who added that the options were circulating at high levels in the Pentagon.

The memo also includes an option to consider reassessing US diplomatic support for longstanding European 'imperial possessions,' such as the Falkland Islands near Argentina.

The State Department's website states that the islands are administered by the United Kingdom but are still claimed by Argentina, whose Libertarian President Javier Milei is a Trump ally. 

Britain and Argentina fought in 1982 over the islands after Argentina made a failed bid to take them. Some 650 Argentine soldiers and 255 British troops died before Argentina surrendered.

Donald Trump has repeatedly insulted Prime Minister Keir Starmer, calling him cowardly because of his unwillingness to join the US war with Iran, ​saying he was 'No Winston Churchill' and describing Britain's aircraft carriers as 'toys'.

Britain initially did not grant a request from the US to allow its aircraft to attack Iran from two British bases, but later ​agreed to allow defensive missions aimed at protecting residents of the region, including British citizens, amid Iranian retaliation.

One option in the email envisions suspending 'difficult' countries from important or prestigious positions at NATO, the official said.