Theresa May faces fight for her leadership as mutinous Tory MPs warn she is ‘drinking in last chance saloon’

Theresa May is facing a fight to save her leadership as mutinous Tory MPs demanded she appears before them to justify her Brexit plans.

The prime minister has been urged to attend a so-called show trial at the 1922 Committee of Conservatives on Wednesday, after last week’s crunch summit in Brussels broke up without a deal on Britain exit terms.

Amid an outpouring of backbench anger, former Brexit secretary David Davis said Ms May had “managed to anger not just Leavers but ardent Remainers as well”, in an article where he set out his own vision for Brexit, and prompted speculation about his leadership ambitions.

It comes as Dominic Raab, his successor, said ministers would not agree to a longer transition period unless Brussels drops its demand for a backstop on the Irish border, following a Tory backlash about plans to keep Britain tied to the EU for another year.

Critics of the prime minister claim the 48 letters needed to trigger a no-confidence vote could soon be reached.

Tory MP Andrew Bridgen told The Mail on Sunday: “This week, Theresa May will find that she is drinking in the last chance saloon and the bad news for her is that the bar is already dry.

“If she doesn’t turn up to the 1922 that will only make the letters go in even faster.”

Tory rising star Johnny Mercer, who prompted a major row when he described the government a “shit show”, said he had received “overwhelming” support from within the party after speaking out.

“I cannot continue to support an administration that cannot function,” he told The Sunday Times.

“We need technocrats and managers – we couldn’t do it without them. But at this defining moment in our history, Britain cannot be led by them.”

Downing Street sources said the prime minister’s diary would be set out on Monday, deciding whether she would address the committee of backbenchers.

Mr Davis, who is considered a possible challenger to the prime minister, made a bullish intervention where he threatened a no-fly zone for EU planes and said Britain “should not allow ourselves to be bullied by the EU”.

Writing in The Mail on Sunday, he warned: “There have been claims that planes will not fly between the UK and EU.

“This is extremely improbable as it would undermine the Spanish and other European tourism markets as well as Mediterranean property markets.

“Furthermore, European flights would still need our airspace in order to fly to the USA. That should be enough to focus minds on a sensible outcome.”

Ms May signalled she would consider extending the Brexit transition period to give negotiators more time to solve problems, including the vexed issue of the Irish border.

However, Mr Raab said a longer transition period should be instead of a backstop on the Irish border, rather than an accompanying proposals.

“The prime minister has rightly refused to rule out considering different approaches – including extending the implementation period, as an alternative to the backstop,” Mr Raab wrote in The Sunday Telegraph.

“But we won’t sacrifice Northern Ireland, and we must have finality to any backstop – whether through a time limit or a mechanism that enables the UK to leave, in case the EU doesn’t live up to its promise to get the future relationship in place swiftly.”

However Brexiteer Steve Baker has lined up plans to block the backstop with changes through a parliamentary showdown.

The former Brexit minister has proposed amendments to a new Northern Ireland bill that would make it a legal requirement for the Stormont Assembly to agree to any plan to treat Northern Ireland differently to the rest of the UK.

The devolved legislature has not sat at Stormont since power sharing broke down in January 2017.