Former Chancellor of the Exchequer George Osborne has told ITV News the Prime Minister should take the option of a no-deal Brexit off the table if she doesn't want Government ministers to quit.
He said: "I think the responsibility now is on Theresa May to take a no-deal Brexit off the table.
"It's only being used to threaten Conservative MPs, it's got nothing to do with the real negotiations in Brussels.
"If she keeps on threatening this ticking time bomb under the British economy, I wouldn't be surprised if some members of the Government won't wear it and quit."
His comments come as Justice Secretary David Gauke told ITV News that he didn't believe leaving the EU without a deal would be "in the national interest."
He said: "I am very concerned about what no-deal would mean for the British people and for the national interest, concerned about the economic impact, concerned about national security, concerned about the impact on the United Kingdom.
"So, I don't believe that leaving without a deal on 29 March would be in the national interest."
Meanwhile in Northern Ireland DUP deputy leader Nigel Dodds said no Brexit deal is better than a bad deal.
Mr Dodds told his party's spring conference in Omagh, Co Tyrone, that they want a Brexit deal, "but we are very clear that a no-deal is better than a bad deal".
He also pledged his support to Mrs May if she makes what he described as "necessary change to the backstop".
"As we leave the EU - for us the guiding star is the union between Great Britain and Northern Ireland," he said.
"We will do nothing to undermine that Union.
"The only way to a majority in the House of Commons is with DUP votes. With necessary changes to the backstop, the Prime Minister will have our support."
Mrs May suffered a humiliating defeat in the House of Commons on Thursday after MPs again voted down her latest Brexit plans.
MPs voted by 303 to 258 against the motion endorsing the Government's approach causing Tory loyalists to turn on the party’s Brexiteers.
Downing Street insisted the Prime Minister would continue with her negotiating strategy, with ministers dismissing Thursday’s vote as no more than a “hiccup”.