Theresa May will face a crunch cabinet meeting later as she tries to win colleagues’ support for a draft Brexit agreement between the UK and EU.
Senior ministers will gather in Downing Street at 14:00 GMT amid calls to reject the deal from both senior Brexiteers and some Remain supporters.
The Democratic Unionists have warned it could lead to the break-up of the UK.
But the BBC’s Norman Smith said No 10 were stressing it had pushed “right to the wire” and “gone as far as we can”.
He said the prime minister would seek to head off the threat of any resignations by telling her ministers that while not perfect, the agreement was as good as it can get.
The PM is continuing one-to-one briefings with ministers on the plans ahead of a full cabinet meeting expected to last three hours.