Theresa May has been told delaying Brexit is “doable” but would lead to Britain getting its own “Trump moment”.
The prime minister faced down an argument over whether the UK was ready to leave the EU on 29 March ahead of a key vote on her deal next week.
Foreign Secretary Jeremy Hunt has hinted a delay is needed even if the agreement is ratified.
Speaking on Sky News, Labour’s shadow Brexit secretary Sir Keir Starmer said keeping Britain in the EU for three more months was “probably doable”.
“This is now necessary because of the position we find ourselves in,” he told the Sophy Ridge on Sunday programme.
Mrs May suffered the largest-ever Commons defeat over her EU divorce deal in January, Tory Brexiteers joining forces with the opposition to torpedo it by 230 votes.
Her own backbenchers have agreed to support it in principle but with a key element removed.
The EU has refused to strip out the “backstop” – the insurance policy to prevent a hard border returning on the island of Ireland – but is examining other legal assurances it can give that the policy will never be used.
But with deadlock remaining in Brussels and no signs from Brexiteers or Mrs May’s confidence and supply partners the Democratic Unionist Party that they will back her deal, she is on course for defeat.
A majority of MPs are thought to support blocking no-deal, which on Wednesday they will get to vote on.
But to stop the UK leaving the EU on 29 March by default without an agreement, a decision would have to be taken to delay Brexit.
A vote on that could come next week on Thursday.
Former Brexit secretary David Davis said one suggested change to the backstop, to set up an arbitration panel, “might” have his support but would depend on the details.
But he told the BBC’s Andrew Marr Show that Mrs May should still keep the UK on course to leave the EU if MPs refuse to back her deal.
If not, he warned: “Britain will get its Trump moment.
“What happens is the British people who voted for this… will see a government walking away, a parliament walking away from a question that they themselves put to the people.
“That will absolutely undermine belief in democracy in this country.”
Foreign Secretary Jeremy Hunt also twice suggested Brexit would have to be delayed even if the deal does get passed next week.
“We have an opportunity now to leave on March 29 or shortly thereafter,” he said on Sunday.
Dominic Raab, the former Brexit secretary who followed Mr Davis out of the job, also piled pressure on Mrs May to “keep the promise that no-deal is better than a bad deal”.
He added Mrs May had “absolutely got to whip the vote to keep our manifesto pledges” to keep no-deal on the table.
The prime minister warned MPs on Friday that Brexit may not happen at all if they reject her deal.
With three weeks until Britain is scheduled to leave the EU, she urged parliament to back her on Brexit and “get it done”.
(c) Sky News 2019: Theresa May told Brexit delay ‘doable’ but would lead to ‘Trump moment’