Theresa May says she intends to make a “bold offer” to MPs in a final attempt to get them to approve her Brexit deal in the next few weeks.
Extra protections for workers are expected to be among the proposals, with Mrs May trying to win over the support of some Labour MPs.
The PM needs to secure cross-party support for her EU Withdrawal Agreement Bill, which will be voted on in June.
This comes after the government’s talks with Labour over Brexit broke down.
A Cabinet meeting on Tuesday is to consider plans for a series of “indicative votes” by MPs to establish which proposals could command a majority.
Brexit had been due to take place on 29 March, but the UK was given an extension until 31 October after MPs three times voted down the withdrawal agreement Mrs May had negotiated with the EU.
This prompted negotiations between the Conservatives and Labour aimed at breaking the Brexit impasse, but they collapsed on Friday without an agreement.
Mrs May announced this week that MPs will vote on her Withdrawal Agreement Bill – which would bring the withdrawal agreement into UK law – in the week beginning 3 June.
If the bill is not passed by Parliament, the default position is that the UK will leave the EU on 31 October without a deal.
The prime minister also promised to set a timetable for her departure from Downing Street following the vote on her deal.
Before the talks with Labour, the prime minister – whose Conservative Party does not have a majority in the House of Commons – failed to get her deal through three times, by margins of 230, 149 and 58 votes.
The DUP, which supports her government on certain issues, opposes Mrs May’s agreement with the EU over its implications for Northern Ireland.
Shadow Brexit secretary Sir Keir Starmer said the government should include a “confirmatory” public vote in the Brexit legislation to “break the impasse”.
Speaking to BBC Radio 4’s Today programme, Sir Keir said Labour would vote against the Withdrawal Agreement Bill, accusing the government of attempting “an experiment” and bringing the UK to “a cliff edge”.
Labour’s preferred plan is for changes to the government’s Brexit deal or an election, but if neither of those are possible, it will support the option of giving the public a say on the deal agreed by Parliament.
Sir Keir blamed the collapse of talks with the government – which lasted six weeks – on the inability to “future proof” a deal against an “incoming Tory leader”.
Mrs May has previously blamed the collapse on the lack of a “common position” within Labour.
Writing in The Sunday Times ahead of June’s vote, Mrs May said she will “not be simply asking MPs to think again” on the same deal that they have repeatedly rejected.
Instead, the PM said she wanted them to consider a “new and improved deal with fresh pairs of eyes – and to give it their support.”
Meanwhile, Tory grandee Michael Heseltine has said he will vote for his local Liberal Democrat candidate in the upcoming European parliamentary elections – in protest at the government’s stance on Brexit.
Lord Heseltine, also writing in The Sunday Times, called on the Tories to back another referendum on Britain’s EU membership in order to avoid what he called “the biggest act of economic self-harm ever undertaken by a democratic government.”