Former Conservative co-chairman Grant Shapps has prepared a list of Tory MPs who are calling on Theresa May to resign.

Speculation has swirled over the Prime Minister’s position following her calamity-ridden conference speech on Wednesday and this year’s General Election result where the party lost its overall majority.

Mr Shapps told Sky News: “As it happened this list has been growing, and this week didn’t help.

There are five former Cabinet ministers, one former minister, and quite a lot of the backbenchers.

We think May is a decent person doing her best but she led us into an election with that result. We’re not pointing any fingers.

He added that the list was pretty much my initiative, saying: I hold the list myself and I know a number of people on the list have texted the Chief Whip directly then informed me.

It’s completely straightforward I’m surprised the whips think it’s a good idea to publicise it, at least people now know where to come.

The former minister’s words come after Mrs May’s main address to Tory delegates in Manchester was interrupted by a comedian brandishing a mock P45 notice.

She also suffered repeated coughing fits, and lettering on a slogan behind her fell down.

Regarding Mrs May’s leadership, Mr Shapps said: If something isn’t working, you have to do something about it. We are very unhappy about the situation.

We don’t want to write a formal letter we don’t want to do make it difficult and embarrassing for Theresa. When the time is right we’ll give the list to Theresa.

Sky’s political editor Faisal Islam said: This is more than just a headache now for the PM. This is a former minister who has gone public.

A large number of Tory MPs have publicly backed the embattled Prime Minister, including Home Secretary Amber Rudd who said the Government would deliver Brexit under Mrs May’s leadership.

In an article for The Daily Telegraph, Ms Rudd said: We, Theresa May’s Government, want to … set out a better path, one that actually leads to a prosperous, secure and united country.

We can do that, and we will under her leadership. She should stay.

But Mr Shapps said the Conservatives must look for a new leader to take us forward.

Critics of the PM were said to be attempting to drum up a delegation of around 30 MPs to tell her she has lost support and must resign.

One Conservative MP told Sky’s political correspondent Tamara Cohen there was a 50% chance the PM would quit by Friday.

They added: It’s a disaster. The question is it a worse disaster if she goes?

Also, former Conservative minister David Mellor claimed Mrs May was a dead woman walking.

Senior Conservatives insist most MPs still believe she should carry on for the sake of the party amid the threat from a resurgent Labour under Jeremy Corbyn.

However, there was said to be growing pressure for a Cabinet reshuffle among loyalists angry at the repeated challenges to her authority by Foreign Secretary Boris Johnson.

Under party rules, 48 MPs would need to write to the party’s backbench 1922 Committee expressing no confidence in Mrs May in order to trigger a leadership contest.