Leading Brexiter Jacob Rees-Mogg has called on Theresa May to suspend parliament if tries to block a no-deal Brexit.
Labour MP Yvette Cooper is leading a cross-party move to get it written into law that the UK cannot leave the EU without an agreement.
Opposition leader Jeremy Corbyn is meeting with Cooper to discuss whether Labour will back her amendment if it is voted on next Tuesday.
Speaking on Wednesday, Rees-Mogg demanded the government take drastic action to stop any such moves passing into law.
He said: “If the House of Commons undermines our basic constitutional conventions, then the executive is entitled to use other vestigial constitutional means to stop it, by which I basically mean prorogation [suspending parliament].
"Prorogation normally lasts for three days, and any law that is in the process before prorogation falls. I think that would be the government’s answer. That is the government’s backstop, to use a choice phrase."
May has repeatedly refused to rule out no deal, arguing the only way to avoid that scenario is to secure an agreement or stop Brexit.
Corbyn has refused to hold talks with the Prime Minister until she rules out leaving without an agreement.
Addressing a meeting of the pro-Brexit Bruges Group in Westminster, Rees-Mogg hit back at suggestions he had ’”softened” his position on the PM’s withdrawal deal – which was defeated by 230 votes in the Commons earlier this month.
He claimed that while he felt May was listening to concerns over the withdrawal agreement, it still needed “fundamental change”.
The high-profile Brexiter added: “As long as that backstop is there, I will not vote for this deal.”
The suggestion if suspending parliament until after March 29 was put to May in the Commons by Tory MP Sir Desmond Swayne on January 14.
She replied: "My right honourable Friend is trying to tempt me down a road that I do not think I should go down."