Theresa May is being forced to ask the EU to delay Brexit and avoid a no-deal divorce on Friday, after a change in the law was rushed through parliament.
The cross-party proposal, which has received royal assent and has become law, was raced through the Commons in a single day last week and completed its journey through the Lords this evening.
Peers made two changes to it that removed a significant sting for the prime minister, which was signed off by the lower house on Monday.
Parliament has rejected versions of the PM's Brexit deal three times
Under the new terms, MPs will still be able to tell Mrs May how long she should ask the EU to delay Brexit for.
But they will not be able to dispute whatever new date Brussels sets and send the prime minister back to ask again.
They also changed the text of the so-called “Cooper Bill” to say Mrs May cannot ask for a date before 22 May.
Britain is on track to leave the EU this Friday – 12 April – but the prime minister has chosen not to pursue a no-deal divorce.
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She has lost three votes on her Brexit deal, with ardent Brexiteers and Eurosceptic Conservatives joining forces to defeat it.
It comes as talks between Mrs May and Jeremy Corbyn to broker a Brexit compromise deal failed to reach a break through.
The Labour leader said that “so far we have not had the undertakings we want in our demands” after the discussions broke down last week.
He vowed they would continue and Downing Street confirmed “technical talks” would re-start this evening.
Corbyn: I’ve got many concerns over deal
Earlier, senior Tory MP Sir Graham Brady confirmed there was no breakthrough “yet”.
He emerged from a personal briefing with the prime minister on “the discussions that have been going on” as senior cabinet ministers traipsed in and out of Downing Street.
Meanwhile Mrs May has held phone calls with the Dutch and Maltese premiers, as well as EU presidents Donald Tusk and Jean-Claude Juncker.
She is due to meet France’s Emmanuel Macron and Germany’s Angela Merkel on Tuesday ahead of a summit of all EU leaders on Wednesday.
EU leaders will meet to discuss the request to delay Brexit on Wednesday
The prime minister will use the trip to Brussels to ask for another delay to Brexit until 30 June – but the other premiers will have the final decision.
Conservative candidates have also been emailed to confirm the party “will be contesting” the European Parliament elections in May “due to the current situation”.
Ministers tonight launched the first step to enshrining the elections in UK law.
A Cabinet Office spokesperson said they still wanted Britain to avoid participating in them, and leave the EU before polling day on 23 May.
The UK may have to hold EU Parliament elections
But they added: “As a responsible government today we have taken the necessary steps required by law should we have to participate.”
Legislation known as a “day of poll order” has been laid in parliament for returning officers presiding over the elections.
“It does not make these elections inevitable as leaving the EU before the date of election automatically removes our obligation to take part,” the Cabinet Office spokesperson added.
A Sky Data poll has also found most Britons think the prospect of the UK leaving with no-deal is unlikely – but many remain worried by the prospect of such a scenario.