Tory grandee Ken Clarke has said he would volunteer himself as leader of a caretaker government in order to stop a no-deal Brexit and he would vote against Boris Johnson in a vote of no confidence.
He claimed the suggestion was silly but said he would do it, "if it was necessary to get us to a more sensible outcome of the present crisis".
However he said the best way to block no deal is through legislation, a route he believes has a "chance" of succeeding.
He said: "I personally think it is possible, yes, I think it could well happen - genuinely."
He said the biggest challenge to succeeding is "organising this cross-party consensus that we've failed to achieve so far, and also maintaining the courage of all those MPs who want to defy the party whip."
His comments come as Prime Minister Johnson's plan to suspend Parliament faces three legal challenges in London, Edinburgh and Belfast.
And in response to an urgent application for a judicial review in London's High Court, a spokeswoman said: "The defendant is the Prime Minister. The application is being considered."
The legal bid in Belfast to injunct Boris Johnson's move was adjourned for 24 hours after being launched by prominent victims campaigner Raymond McCord, who was also already pursing legal proceedings against the potential proroguing of Parliament.
On the other hand Leader of the House of Commons Jacob Rees-Mogg described the outrage at the suspension of Parliament as “phoney”.
The leading Brexiteer and Johnson ally also hit back at Commons Speaker John Bercow’s intervention on the decision to prorogue Parliament, saying it was “not constitutional” for him to speak out in such a way.
Mr Rees-Mogg insisted the move to prorogue Parliament for almost five weeks was not undemocratic and "fully in line with the constitution".
And, Lord Young, the government whip in the Lords, also quit, saying: “I am very unhappy at the timing and length of the prorogation", adding that it risks "undermining the fundamental role of Parliament”.
But Mr Rees-Mogg said: “I think the outrage is phoney and it is created by people who don’t want us to leave the European Union and are trying very hard to overturn the referendum result and don’t want the benefits of leaving the European Union.”
He added: “Parliament wasn’t going to be sitting for most of this time anyway. This is completely constitutional and proper.”