Labour leader Jeremy Corbyn has told MPs he will table a motion of no confidence in British Prime Minister Theresa May over her handling of the Brexit deal vote.
Earlier, Mr Corbyn accused Theresa May of leading Britain into a "national crisis" over Brexit, as he warned her deal has lost Cabinet support.
Replying to a statement from Mrs May, the Labour leader said: "We face an unprecedented situation - the Prime Minister has led us into a national crisis.
"If any more evidence was needed of why we face this grave situation, the Prime Minister demonstrated it at last week's summit.
"There were some warm words drafted and the Prime Minister even managed to negotiate those away to be replaced by words about preparing for no deal."
Mr Corbyn said the "cold reality" was Mrs May achieved "nothing" last week after returning to Brussels to seek further assurances over the Irish border backstop.
He went on: "The deal is unchanged and not going to change. The House must get on with the vote and move on to consider the realistic alternatives."
Mr Corbyn accused Mrs May of cynically running down the clock on the March 29 Brexit deadline.
Mr Corbyn demanded Mrs May answer three questions as he quizzed her over the latest Brexit negotiations.
He said: "One, does her deal still have the confidence of the Cabinet?
"Two, is Cabinet collective responsibility still in operation?
"Three, does it remain Government policy to avoid a no-deal outcome?"
