Video report by ITV News Political Editor Robert Peston
Prime Minister Theresa May has told the House of Commons that Tuesday's vote on her Brexit deal is being "deferred."
MPs roared with laughter when she told them she had "listened very carefully" to what had been said in the chamber, explaining her bid to delay the vote.
Announcing the decision to delay the vote on the Brexit deal, Mrs May told the Commons that if it had gone ahead as planned, the Government would have been defeated by a significant margin.
Alluding to the main point of concern about her deal she said the Northern Ireland backstop is causing "widespread and deep concern."
In place of the vote, Mrs May will travel to The Hague in the Netherlands on Tuesday for a bilateral meeting with Dutch PM Mark Rutte - a bid to shore up support for her ailing deal.
But MPs have secured an emergency debate on Mrs May's decision which will take place in the Commons on Tuesday - an application brought about by Labour leader Jeremy Corbyn.
Speaking in the Commons on Monday, Mrs May said the Government was stepping up preparations for a no-deal Brexit.
"I have listened very carefully to what has been said in this chamber and out of it by Members from all sides," she said.
"From listening to those views it is clear that while there is broad support for key aspects of the deal, on one issue, the Northern Ireland backstop, there remains widespread and deep concern.
"As a result, if we went ahead tomorrow it would be rejected by a significant margin."
Commons Speaker John Bercow called the Government's plan to delay a vote on the Brexit deal "deeply discourteous".
He urged the Prime Minister to hold a vote on the matter before "unilaterally" deciding to postpone MPs having their say, saying it would be the "courteous, respectful and mature" thing to do.
What happens next?
Video report by ITV News Political Correspondent Paul Brand
Mrs May will meet her EU counterparts ahead of an EU summit on Thursday and Friday.
She told MPs: "I am clear from what I have heard in this place and from my own conversations that these elements do not offer a sufficient number of colleagues the reassurance that they need.
"I spoke to a number of EU leaders over the weekend and in advance of the European Council I will go to see my counterparts in other member states and the leadership of the Council and the Commission. I will discuss with them the clear concerns that this House has expressed."
She said the Government was also looking at "new ways of empowering the House of Commons" to ensure that any provision for a backstop has "democratic legitimacy and to enable the House to place its own obligations on the Government to ensure that the backstop cannot be in place indefinitely".
How will the vote be deferred?
The Prime Minister's official spokesman explained the procedure by which the Brexit vote will be deferred.
When the Commons clerk reads out the orders of the day on Monday evening, the Government whip will call out "tomorrow". This puts off the two remaining days of debate and any votes until a date yet to be fixed.
There is no requirement for vote on this procedure, said the spokesman.
How did the Commons react to Mrs May's announcement?
Shouts of "resign" were heard from the Labour benches as Theresa May concluded her statement to the Commons on Brexit.
Labour leader Jeremy Corbyn said: "We are in an extremely serious and unprecedented situation.
"The Government has lost control of events and is in complete disarray."
It is understood that the PM had been warned that she faced a large-scale defeat when MPs voted at the end of five days of debate in the Commons on her plans.
She spoke with her Cabinet colleagues by a telephone conference call before addressing the Commons.
Liberal Democrat leader Sir Vince Cable said he would support a no confidence vote.
"With the fiasco today, the Government has really lost all authority," he said.
"Let me just say that I and my colleagues will fully support the Leader of the Opposition (Mr Corbyn) if he now proceeds to a no confidence vote, as duty surely calls."
Labour later said it would put down a no confidence motion "when we judge it most likely to be successful".
The Commons went into full "pantomime" mode as Tory former minister Anna Soubry warned the Prime Minister that "nothing will change" in the EU's approach to negotiation.
Mrs May dodged questions from her own benches about how and when she would be rearranging the meaningful vote.
Tory Remainer and former education secretary Justine Greening asked whether she intended on pushing back the date as far as March 28 next year - the day before Brexit Day.
Mrs May said: "I do not believe the scenario she has set out is the correct one... I believe it is right we should be recognising the concerns raised in this House and attempting to find a way through those concerns and to resolve those concerns."
Tory Brexiteer Peter Bone said Mrs May asked whether the vote would be rearranged using a procedure allowing a vote or just "an anonymous whip" pushing it through with one word.
She responded: "I believe it's important for the Government to be listening to the comments that have come to us in relation to this specific issue and to be responding to those comments if we want to ensure we get a deal over the line that's good for the British people."
What have other leaders said?
Irish Prime Minister Leo Varadkar ruled out reopening negotiations around the backstop, which is designed to keep the Irish border open following Brexit.
The Taoiseach said it was not possible to reopen any aspect of the Withdrawal Agreement without reopening all aspects of it.
Ahead of her statement, Mrs May spoke by phone to Arlene Foster, leader of the Democratic Unionist Party, whose MPs prop up the minority Conservative administration but were threatening to vote against her deal.
Mrs Foster said: “My message was clear. The backstop must go. Too much time has been wasted. Need a better deal. Disappointed it has taken so long for Prime Minister to listen.”
And she spoke to Scottish First Minister Nicola Sturgeon, who said she told the PM that “delaying the vote is an abdication of responsibility, leading to even greater chaos”.
Guy Verhofstadt, the European Parliament's Brexit coordinator, tweeted that he "can't follow" the developments anymore.
"Just keep in mind that we will never let the Irish down," he said. "This delay will further aggravate the uncertainty for people & businesses. It's time they make up their mind!"
EU Council president Donald Tusk reiterated that the bloc "will not renegotiate" the deal.
Green MP Caroline Lucas tweeted: "You can't run from democracy, Theresa May.
"PM's Brexit deal is destined to fail and she's grasping at straws to stay in power - but it's clearer than ever she's lost control. We no longer have a functioning Government. Parliament must deliver a Peoples' Vote now."
In the wake of reports the Brexit vote had been called off, sterling fell 0.4% against the US dollar to 1.26. Against the euro, the pound was down 0.6% at 1.10.