The foreign secretary said it was "unrealistic" to think MPs would not block Britain crashing out of the EU without a deal if they wanted to - contradicting Theresa May's claim that her deal is the only alternative to a no-deal outcome.
In a further sign of cabinet splits, Amber Rudd, the work and pensions secretary, refused to rule out resigning if the government pursues a no-deal Brexit.
To follow events as they unfolded, see out live coverage below
Welcome to today's live coverage from Westminster.
Jeremy Hunt has admitted that MPs would be able to stop a no-deal Brexit even if the government decides to opt for one
Richard Leonard, leader of Scottish Labour, has refused to say whether his party would campaign for or against Brexit in a future general election.
Jeremy Corbyn also refused to answer the question yesterday, saying it would be for the party's policy making process to decide.
Mr Leonard told BBC's Good Morning Scotland:
"It's not a matter of campaigning for or against Brexit.
"There has been a referendum in which people overall decided that we should leave the European Union and I have said repeatedly that I think the job of elected politicians is to look at the best way of extracting the best deal under those circumstances.
"Our policy on Brexit so far has been to try to secure the best deal. The manifesto of the Labour Party will be decided by the Labour Party and we've got a process for determining that.
"My view is that we had a referendum in 2016, our job has been to try to get the best deal."
Amber Rudd has refused to rule out resigning from the cabinet if the government pursues a no-deal Brexit.
The work and pensions secretary said she was "committed" to ensuring the UK does not leave the EU without a deal.
This on this morning's No 10 briefing with Westminster journalists, from political editor Joe Watts...
Downing Street wanted to make clear that it is not government policy to extend Article 50.
Theresa May’s spokesman said that the prime minister had ruled out the possibility last Sunday on the BBC’s Andrew Marr show and in the Commons during the week. In truth the PM was more equivocal on Wednesday at least.
Certainly when she was asked about an extension by ex-chancellor Ken Clarke, she chose to talk about the position of parliament and her deal more broadly, instead of offering a direct answer.
Then you have the Evening Standard today running comments from a senior minister saying: “The legislative timetable is now very, very tight indeed.
“Certainly, if there was defeat on Tuesday and it took some time before it got resolved, it’s hard to see how we can get all the legislation through by March 29.”
The reality of the legislative timetable is hard to escape and the practicalities of it do push you towards the inevitable conclusion that an extension will be necessary.
One senior Tory told me earlier this week that even if the deal is voted through, the UK may need a few extra weeks grace to get the legislation through.
So we do seem to be heading towards a later Brexit day than March 29. It increasingly feels like the line from Downing Street that in is “not government policy”, is missing the words “at the moment” at the end of the sentence.
A rare moment of solidarity between Tory Remainers and Brexiteers in the Commons chamber just now...
Theresa May has called trade union leaders in a last-ditch bid to secure fresh support for her Brexit deal ahead of Tuesday's crunch vote
Two of the biggest donors to the Brexit campaign have said they are now expecting the UK to stay in the European Union.
Peter Hargreaves and Crispin Odey, who both donated huge sums to the Leave campaign in 2016, have claimed they believe the decision to leave the bloc will be reversed.
Changes to the benefit system that will see more money go directly to women who are the "main carer" in a family will be introduced later this year, Amber Rudd said.
The Work and Pensions Secretary said she had listened to arguments from advocacy groups that the system of "one payment per household" penalised women.
Charities have argued that often this means a whole family's benefit payments go to the man's account and often women - including victims of domestic violence - have little or no access to it.
In a speech at a JobCentre in south London, Ms Rudd said that "women can never be truly free until they have economic independence".
She said that while the one-payment system was "established" she recognised the validity of claims made by Refuge, Women's Aid and others "about how the current structure of household payment penalises women".
She said: "That is why I am committed to ensuring that household payments go directly to the main carer, who is usually - but not always - the woman.
"For those couples currently claiming UC (Universal Credit) around 60% of payments already go to the woman's bank account.
"However I am looking at what more we can do to enable the main carer to receive the UC payment and will begin to make those changes later this year."
John Bercow has shown he will play a pivotal role in the Brexit endgame, writes Independent political commentator Andy Grice.
Read his column here:
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