Olivier Cadic, who accompanied France’s Europe Minister during her visit the London this week, said British MPs and the government must realise options are now limited: “It’s a brutal no-deal Brexit, the deal, or otherwise they must have the courage to vote to cancel Brexit or hold another referendum.”

However he said he still cannot believe the British will “jump over the cliff in three weeks’ time”.

The EU leaders have a feeling of "astonishment" over the current impasse, Mr Cadic said.

“What bothers the Europeans a lot is that the form of backstop that was agreed was not originally what the Europeans wanted and she forced their hand saying it was the only one that was acceptable to the UK parliament and if they wanted the parliament to sign it off the backstop had to be like that.

“They’ve been discussing the subject for a whole year – the other priorities were citizens’ rights and the amount of the money that was quite easily validated. The problem of the backstop is what we are still stuck on.

“The 27 are very ill at ease because May said it must be her form of backstop to be acceptable – they accepted, but then we all saw it was a catastrophe. We saw this vote by the British MPs [with a large majority against the deal] that also took 30 days to happen, so we lost a month. Now there are zero new proposals, and what’s worse is they are coming back with proposals that have already been refused last year. The issue now when the UK speak to us is to know whether it’s really what the parliament wants.”

Mr Cadic said everything will hinge around what happens in the British parliament next week and at the EU summit the following week on March 21-22. He does not expect EU leaders to agree to an extension if there is not a very clear reason for it. “The British parliament must decide, it’s up to them. If they just say ‘we can put it off’ then the EU will ask what is it for? Is it just to find ourselves in the same mess in three months’ time?”

He added the uncertainty has meant the 27 states have been obliged to “prepare for the worst” – a “brutal”, no-deal Brexit – even though it is not what they want.

“They see that the problem is on Theresa May’s side. The UK is always trying to put the ball back in Europe’s court. But Nathalie Loiseau was very clear that we can’t continue with this ambiguity. On the EU side they just want to know ‘what do you want?’.”

Mr Cadic said the idea of time limiting the backstop is like saying you can take out insurance for a period for your car but then the cover stops after a certain time and you drive with no insurance. “It’s not acceptable to block the 27 like that,” he said.

“It’s time for a decision. The UK parliament continues to say what it doesn’t want, but not what it wants, which was also the case with the Brexit referendum decision itself – it was a rejection but without a constructive project.”

The EU are keen to move on with other matters such as EU reforms, which was why Mr Macron wrote an open letter recently, he said. The Brexit referendum vote had “showed there are things that don’t work”, however the EU leaders feel the Brexit process is now blocking further progress.

“We must move on and the EU are fed up and feel nothing is being achieved. Only the British parliament can decide now yet Theresa May – I think she’s doing it on purpose – said it’s up to Europe.”

“Ultimately, I think Mrs May misread the psychology of the EU leaders."

He added: “Nathalie Loiseau said that Nigel Farage once said his aim was twofold – to get the UK out of the EU and to destroy the EU. If the first has to happen, so be it, but it he manages the second, that’s not OK. That’s why the EU has to be firm at this stage. The future of the EU is at stake.”

Mr Cadic said the idea of ring-fencing citizens’ rights – “taking the rights of the five million out of the rest of the agreement” – was complicated because the withdrawal agreement is designed to be one coherent whole. However he said he believes that one way or another citizens’ rights matters will be worked out.