An anti-Brexit demonstrator walks outside the Manchester Central Convention Complex where the Conservative Party Conference 2019 takes place, in Manchester, Britain, on Sept. 29, 2019. British Prime Minister Boris Johnson ignited the Brexit debate Sunday, saying Britain will leave the European Union next month despite a parliamentary bill forcing him to seek an extension from Brussels if there is no deal. Johnson made his pledge in a television interview in Manchester as thousands of Conservatives arrived for the start of the last big party conference of the year. (Photo: Xinhua)

British Prime Minister Boris Johnson launched a charm offensive on Friday to sell his Brexit deal to sceptical MPs, with a looming vote in parliament resting on a knife-edge.

The Conservative leader pulled off a major coup in agreeing a new divorce deal with the European Union on Thursday, paving the way for him to deliver his promise to leave the bloc on October 31.

But the agreement must still be approved by the House of Commons, which is meeting for the first time on a Saturday in 37 years to debate the text - and many MPs are strongly opposed.

Johnson told a Brussels press conference late Thursday that he was "very confident" of getting the accord through - although analysts suggest the vote could be very tight.

Johnson has no majority among MPs, opposition parties have come out against the deal and even his parliamentary ally, Northern Ireland's Democratic Unionist Party (DUP), says it cannot support the terms.

If the Commons rejects the deal, Johnson will be forced by law to ask the EU to delay Brexit, for what would be the third time. He has said he would rather "die in a ditch" than do so.