The prime minister is to urge MPs to give her more time to secure changes to her Brexit deal.
Theresa May is expected to pledge in the Commons this week that MPs will get another say on Brexit if she cannot recommend a revised plan this month.
Meanwhile, shadow Brexit secretary Sir Keir Starmer told the Sunday Times that Labour plans to force another vote on her deal anyway.
He said the move was necessary to stop Mrs May “running down the clock”.
With 47 days until the UK is due to leave the European Union, some ministers have considered resigning so they could support backbench proposals to force the government to delay Brexit.
But Downing Street aims to reassure them by promising another vote where they can put forward alternative options, if a new deal has not been struck by 27 February.
Mrs May has been seeking legally binding changes to the plans for avoiding a hard border in Ireland.
‘Pretending to make progress’
Critics of the current plans say they could tie the UK to EU rules indefinitely or mean Northern Ireland ends up under a different system to the rest of the UK.
But the Irish government and the EU have repeatedly rejected calls for changes.
If Mrs May does not succeed by the end of the month, MPs will be told they can put forward alternatives such as extending the deadline for the UK’s departure from the European Union from 29 March.
Speaking to the Sunday Times, Sir Keir Starmer accused the prime minister of “pretending to make progress” over issues such as the Irish border.
He said that Mrs May intends to return to Parliament after the 21-22 March European summit – with just one week before Brexit – and offer MPs a choice between her deal and a no-deal Brexit.
“We can’t allow that to happen. There needs to be a day when Parliament says ‘that’s it, enough is enough’,” Sir Keir said.
Sir Keir called the prime minister’s approach “reckless” and “blinkered”, blaming “tunnel vision” for the defeat of her Brexit deal by a record 230 votes in January.
Labour intends to put forward an amendment that will require the prime minister to hold a new vote on her deal by 26 February.
He said: “We have got to put a hard stop into this running down the clock. And that’s what we want to do this week.”