UK Parliament Speaker John Bercow blocked Boris Johnson from holding a vote Monday on his new Brexit divorce deal, two days after MPs scotched the British prime minister's attempt to pass it.
Lawmakers decided at their first Saturday session since the 1982 Falklands War to force the Conservative leader to ask Brussels to postpone the October 31 divorce by three months.
"The motion will not be debated today because it would be repetitive and disorderly to do so," Mr Bercow said.
Mr Johnson is trying to secure a break from Brussels that severs many of the island nation's economic relations with Europe after 46 years of EU membership.
But lawmakers refused on Saturday to give their backing to his revised divorce plan until all the domestic legislation needed to ratify it has passed.
Mr Johnson's foes are now forging new alliances and trying to attach amendments that could either force him to push for closer trade ties with the EU - or abandon the deal and accept a third delay this year.
But Mr Bercow's decision does not kill the deal, which could appear before the house again later in the week, holding out the possibility that Britain could still leave the EU in an orderly fashion on 31 October.
Here are the possible scenarios:
Delay
Legislation passed last month stated that unless MPs backed a Brexit deal by the end of 19 October, Mr Johnson must write to EU leaders asking for Brexit to be postponed for three months to January 2020.
If the EU offers a different date, Mr Johnson must accept it unless he can persuade the House of Commons to vote against the plan.
The prime minister sent the letter, and EU leaders on Monday were considering their response.
Mr Johnson hopes that they will rule out an extension, or offer only a "technical" delay to allow parliament time to pass the legislation should the deal be approved.
He appears to have an ally in President Emmanuel Macron, with a French government spokeswoman saying on Monday a delay was "in nobody's interest."
But German leader Angela Merkel seems more amenable to a longer extension, with reports suggesting that they could agree to a final delay until February.
Deal passes?
Even if the EU agrees to an extension, Mr Johnson could still get Britain out on 31 October by swiftly ratifying his Brexit deal.

British Prime Minister Boris Johnson with EU leaders during a Brexit summit in Brussels, 17 October 2019. Source: AAP
Several of those who backed Saturday's amendment say they would support Mr Johnson's bill, once the threat of a "no-deal" is removed.
Eurosceptic members of his Conservative party have also pledged to back the legislation.
However, there is a risk the bill is hijacked by anti-Brexit MPs, for example, to make approval subject to a new EU referendum.
Timing could also be an issue. Legislation of this type would normally take months but the Houses of Commons and Lords would have less than two weeks.
'No-deal' Brexit?
The default legal position is that Britain leaves the EU on October 31 unless the other 27 member states agree to a delay.
Business and markets across Europe fear the shock of a sudden Brexit that even the government's own assessment says would cause economic damage, raising the chances that the EU will offer an extension.

Protesters in an anti-Brexit, 'Let Us Be Heard' march on Piccadilly in London, as they head to Parliament Square. Source: Matt Crossick
Another election?
Riding high in the polls, Mr Johnson has already tried twice to get an early general election to try and win back a majority in parliament.
But he needs the support of the main opposition Labour party to call one.
Labour says it will back an election when the threat of a "no-deal" Brexit is off the table.
A second referendum?
Labour says any deal should be subject to a new referendum and has promised to call one if it takes office.
Some MPs may try to force the issue during the passage of the Brexit deal legislation, although it is far from clear that they have the numbers to succeed.