Parliament resumes today, with heightened speculation of a vote of no-confidence or even a call for a general election.
Conservative MPs have been warned they will lose party support if they vote against the government.
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16.00 - Phillip Lee defection cuts government’s working majority to zero
Dr Phillip Lee has defected from the Conservative Party to the Liberal Democrats and said the government is “aggressively pursuing a damaging Brexit in unprincipled ways”.
While Boris Johnson was addressing the House of Commons Dr Lee crossed the chamber.
In a statement he accused the government of “putting lives and livelihoods at risk unnecessarily” and “wantonly endangering the integrity of the United Kingdom”.
“I believe the Liberal Democrats are best placed to build the unifying and inspiring political force needed to heal our divisions,” he said.
Liberal Democrats leader Jo Swinson said she was “delighted to welcome” Dr Lee to the Lib Dems.
“He brings almost 10 years of parliamentary experience and decades of professional expertise. He shares our commitment to prevent a disastrous no-deal Brexit, and to stop Brexit altogether,” she said.
It is the first time a government has lost its majority in office since John Major in 1997.
14.30 – Rory Stewart pens essay on the dangers of no deal
Rory Stewart has written a lengthy article that supports a “sensible Brexit deal” and has rubbished no deal as a “failure to reach a destination”.
In the essay and accompanying video he said no deal would be perceived around the world as a “signal failure of sense, statesmanship, and strategy”.
“We would drop overnight into the margins of the world’s trading system. We would have left all the fundamental questions, about our future, unresolved and uncertain. And our reputation, prosperity and influence would be damaged for no benefit,” he said.
“There is no transition under no-deal. We literally crash out on November 1st with nothing in place – with the Irish border issues, our payments to the EU, and citizens’ rights unresolved.”
He said the argument put forward by Boris Johnson and Jacob Rees-Mogg the UK could rely on a WTO trade agreement is viewed by trade experts as “nonsense – inapplicable, unacceptable to the EU, and unenforceable”.
Mr Stewart has pledged to be one of the Conservative MPs who will risk their place in the party to vote against the government on a Bill to prevent a no-deal Brexit.
Less than three months ago he came fifth in the race to become the Tory leader.
13.45 - Jeremy Corbyn accuses PM of ‘riding roughshod over Parliament’
Jeremy Corbyn said he “fully expects” Labour MP Hilary Benn’s Bill to prevent a no-deal Brexit will pass Parliament.
The Labour leader said the Bill should pass the House of Commons on Wednesday before going to the Lords and becoming law.
“We do believe we have the MPs here and ready to support that legislation because many are alarmed at the consequences for jobs, for our economy, of crashing out on October 31 without a deal, which is what the Prime Minister seems determined to try to do,” he said.
“That's why Parliament asserting itself on behalf of those people who don't want us to crash out is important.”
Downing Street said the Bill was a “blueprint for legislative purgatory” and was “very clearly in Brussels' interests not in the British interest”.
The Prime Minister’s spokesman said: “We are opposed to the Bill which is being brought forward because it is about crippling negotiations and chopping the legs out from under the UK position, and making any further negotiation impossible.”
Mr Corbyn declined to set a date for a no-confidence vote in the government if the no deal legislation fails.
He said: “I will choose a time, but you will know soon enough”.
12.00 - Ian Blackford to use snap election to call for Scottish referendum
Ian Blackford has said an October general election would be a “fantastic opportunity” for Scots to demand a second independence vote.
The SNP’s Westminster leader said if Boris Johnson called a snap poll his party’s priority would be to allow Scots to “determine their future”.
The SNP is set to vote against the government and support a Bill that would block a no-deal Brexit and seek an extension until January 31 unless a deal can be made.
Senior government sources have suggested if this vote is successful Mr Johnson would call for a general election on October 14.
Mr Blackford said: “If we take away that risk of leaving the EU at the end of October, let's have that election, let's give the people the right to have their say on where we stand.
“I think there is a very clear difference with what is happening in other parts of the United Kingdom and what is happening in Scotland - the people in Scotland don't want to leave the European Union.”
11.00 - Sam Gyimah says defying PM 'the right thing to do'
Sam Gyimah has said he will vote against the government to support Labour MP Hilary Benn’s Bill to prevent a no-deal Brexit.
He said he will defy the Prime Minister “because it is the right thing to do” and he has no mandate for a “damaging and disorderly Brexit”.
“The Bill today gives the Prime Minister time to get the deal he says he wants, but if he fails then it will compel him to ask for an extension instead of crashing out without a deal,” he said.
He said the argument put forward by some Conservative MPs that no deal must remain on the table as a negotiating tactic “just doesn’t make sense”.
“You can’t on the one hand say no deal is vanishingly inexpensive and would only lead to bumps on the road to UK audiences, and then on the other say it is so terrible that it would force the EU to abandon Ireland,” he said.
09.00 – Justine Greening slams Boris Johnson
The former Education Secretary has launched a blistering attack on Boris Johnson and announced she would stand down at the next election.
She said her concerns the Conservative Party was morphing into The Brexit Party had “come to pass” and Mr Johnson would offer the country a “lose-lose” situation with a general election.
“I want to focus on making a difference on the ground on social mobility and I believe I can do that better outside Parliament than inside Parliament,” she said.
She said a “far better way” to resolve the Brexit deadlock was a second referendum instead of a “messy” election that may prove “inconclusive”.
On Monday the Prime Minister said “I don't want an election, you don't want an election” but government sources later said an October 14 vote could be considered if Parliament votes to block a no-deal Brexit.