Brexit turmoil: Staffordshire MP Sir Bill Cash joins calls for confidence vote on Theresa May

But Sir Bill appears to be in the minority in the West Midlands as Conservative MPs in the region rallied behind Mrs May, as the beleaguered Prime Minister continues to cling to power in the fallout over her Brexit deal with the EU.

The threat to her leadership appeared to have eased slightly today after Mrs May said she did not believe enough letters had been filed by disgruntled Tories to force a confidence vote in her.

However, her position remains extremely precarious amid huge doubts how she will get her Brexit deal through Parliament. There is also the threat of more resignations from her Cabinet if the so-called gang of five seeking to persuade her to alter her plan fail to get what they want.

Many Tory MPs in the region have thrown their weight behind the PM, including minister Margot James, who represents Stourbridge, Stafford MP Jeremy Lefroy and Dudley South's Mike Wood. Even Brexiteer Michael Fabricant, the Lichfield MP, who has criticised the Brexit plan, has confirmed he will not be submitting a letter.

Defence Secretary and South Staffordshire MP Gavin Williamson, who attended the crunch Cabinet meeting that led to the revolt, insisted on Friday he was fully behind Mrs May, as did Aldridge and Brownhills MP Wendy Morton.

Just 48 letters are needed to force a vote on the PM's future. More than 20 MPs have gone public about the fact they had sent letters. The Prime Minister's immediate position, and if she has staved off the threat for now, is likely to be made clearer tomorrow.

See also:

• May takes swipe at Tory critics ahead of ‘critical’ week for Brexit

• Raab accuses PM of failing to stand up to ‘Brexit bullies’ in Brussels

• Brexit meltdown: See what your MP has to say as Parliament in turmoil

Comments from Stone MP Sir Bill were a reminder of a very real threat to her leadership remains.

He told the Express & Star: "This withdrawal agreement is full of broken promises. We would not control our own laws. Decisions would be taken by member states, we wouldn't even be at the table, we would be subject to EU laws.

"Dominic Raab resigned for the same reasons I am giving. It puts Northern Ireland into a different territory and we were told over and over again that the union was precious."

Mr Fabricant said that despite his reservations over the deal, getting rid of the Prime Minister was not the way to go but warned he would vote against it if concessions weren't made.

He said: "I am not putting in a letter to the 1922 to trigger a confidence vote. Unwise. If she won convincingly, and she might, it would strengthen Remainers' hands in the Government. However, this deal as it stands is unacceptable. If unchanged, I will vote against it."

Stourbridge MP Ms James, who serves as digital minister in Mrs May's Government, launched a remarkable attack on leading Brexiteers, including Jacob Rees-Mogg, on Friday, labelling those trying to oust her as 'beneath contempt'.

Mrs May remained defiant today. Asked whether Sir Graham Brady - chairman of the 1922 Committee - had received the 48 letters needed she replied: "As far as I know, no - it has not."

She added: "It is not going to make the negotiations any easier and it won't change the parliamentary arithmetic."