Holding another referendum on the EU would “break faith with the British people”, Theresa May will warn MPs.
Former PMs John Major and Tony Blair are among those urging a new referendum if MPs cannot agree on a way forward.
But PM will argue that it would do “irreparable damage to the integrity of our politics” and not settle the issue.
No 10 said it had “no plans” for votes on other Brexit outcomes if the PM’s deal is rejected after it emerged David Cameron was advising his successor.
The BBC understands Mr Cameron has been speaking to Mrs May about how a series of “indicative votes” on various different Brexit outcomes may be handled if there is deadlock over the terms of the UK’s exit.
Downing Street said Mrs May, who called off a Commons vote on her Brexit deal last week, was focused on getting the extra assurances MPs needed to finally back it next month.
The UK is due to leave the EU on 29 March 2019 – the deal sets out the terms of exit and includes a declaration on the outline of the future relations between the UK and the EU. But it only comes into force if the UK and European Parliaments approve it.
The prime minister has signalled MPs will now vote on this early next year, and no later than 21 January.
But Labour and other opposition parties, as well as some Tory Brexiteers say a decision is needed now, so alternative options can be considered if Mrs May’s deal is rejected.
They are seeking to force a vote before the Christmas recess begins on Thursday, although the BBC’s Norman Smith said it was not clear how they could do this.
Potential “Plan B” options include:
- pursuing different Norway or Canada-style arrangements with the EU
- leaving on the basis of a “managed no deal”
- delaying Brexit to restart negotiations
- hold a fresh referendum
Calls for another referendum have grown in recent weeks amid signs a majority of MPs are opposed both to the deal on the table but also leaving the EU without any kind of agreement.
Mr Blair said last week that after 30 months of negotiation, giving the final say to the people would become the “logical” outcome if there was a deadlock and every other option had been exhausted.