MPs will vote on Theresa May's Brexit deal later after she secured "legally binding" changes to it following last-ditch talks with the EU in Strasbourg, the BBC reports.
The PM said the changes meant the Irish backstop - the insurance policy designed to avoid a hard border in Ireland - could not "become permanent".
But Labour leader Jeremy Corbyn said the changes were not "anything approaching" what she had promised.
Mrs May is expected to chair a cabinet meeting on Tuesday morning before the motion is debated in the Commons in the afternoon and votes are held in the evening.
After talks with European Commission president Jean-Claude Juncker on Monday evening, the prime minister said she "passionately believed" her Brexit deal addressed concerns raised by MPs.