MORE than half of grassroots Conservative members want Theresa May's Brexit Plan to be ditched in favour of a no-deal, a survey suggests today.

As the Prime Minister enters the most crucial period of her premiership with the crunch Commons vote on the proposed UK-EU deal due in less than two weeks’ time, some 57 per cent of the Tory rank and file say they are convinced that leaving the EU without a deal is better than their own leader's Brexit Plan, according to a poll funded by the Economic and Social Research Council.

Less than a quarter, 23 per cent, would vote for Theresa May's deal in a three-way referendum between the deal, no-deal and remaining in the EU.

Professor Tim Bale, who lead the research, said the latest findings were bad news for the PM’s hopes of winning support for her deal.

"If Theresa May is hoping that her MPs will return to Westminster having been persuaded by their constituency associations to back her Brexit deal, she's going to be disappointed. It appears that those members are in no mood for compromise,” he declared.

"Moreover, the Tory rank and file, it seems, are convinced that no-deal is better than May's deal."

Prof Bale went on: "Tory members' dislike for the PM's deal really comes out when we asked about a referendum in which the choice came down to her deal or no-deal.

"Only 29 per cent of Tory members would vote for Mrs May's deal compared to 64 per cent, who would vote to leave without a deal.

"But that's as nothing to Conservative Party members faced with a referendum offering just two choices: remain or no-deal. Some 76 per cent of Conservative Party members would plump for no-deal."

The academic suggested there were two specific issues behind the opposition to Mrs May's deal: the Irish backstop and a belief that fears of disruption from a no-deal were "exaggerated or invented".

The survey also suggested that 44 per cent of Tory members think the PM should quit if MPs voted to reject her Plan.

The PM returned to her Downing Street desk yesterday following the Christmas break and is understood to have already had one conversation with Germany’s Angela Merkel and is due to speak with Mark Rutte, her Dutch counterpart, and Donald Tusk, President of the European Council, in the next 24 hours in her bid to get a “legal lock” to ensure the temporary nature of the backstop.

However, Brussels made clear the UK-EU deal would “not be renegotiated” and confirmed "no further meetings are foreseen" with the UK.

Next week, Mrs May will continue her Westminster charm offensive, inviting every Tory MP to Downing St for a drinks reception on Monday or on Wednesday ahead of the Commons debate on her Brexit Plan and the key vote the following week.

In parallel, Stephen Barclay, the Brexit Secretary, will spearhead a Government “health and travel publicity blitz” on social media and the radio, warning people to get ready for the prospect of Britain crashing out of the EU without a deal; a prospect David Mundell, the Scottish Secretary, has said would be “catastrophic”.