UK Parliament in rare Saturday session for vital Brexit vote

British lawmakers are holding their first weekend sitting in almost four decades to vote on whether to approve Prime Minister Boris Johnson's Brexit deal with the European Union and finally let the UK leave the bloc at the end of this month.

At least, that's the government's plan. Some lawmakers have other ideas, and may yet delay the final decision — more than three years after British voters opted to leave the 28-nation bloc.

Since striking a deal with the 27 other EU nations on Thursday, Johnson has been imploring and arm-twisting both Conservative and opposition lawmakers as he tries to win majority support for his deal.

Johnson's Conservative Party holds only 288 seats in the 650-seat House of Commons, so he will have to rely on support from other parties and independent lawmakers to get over the line.

The result looks set to be close, although Johnson has had some success winning over both hard-core Conservative Brexiteers and a handful of opposition Labour lawmakers who represent pro-Brexit parts of the country.

Opposition parties and Johnson's own Northern Irish allies have rejected the text but the prime minister and his team have spent the past 48 hours frantically trying to win MPs' support.

Johnson could also face opposition from eurosceptics who fear his deal will not fulfil their dreams of abolishing decades of EU rules and regulations from British life.

Northern Ireland's Democratic Unionist Party, which props up Johnson's minority government, will vote against it because of its arrangements for the British province.

The main opposition Labour party meanwhile warns the deal could lead to only a loose trading relationship with the EU after Brexit, which could damage the economy and lower environmental and labour standards.

EU leaders in Brussels this week urged lawmakers to back the deal, to allow both sides to move on to discussing their future relationship.

“This deal means there is no need for any kind of prolongation,” European Commission President Jean-Claude Juncker said.

Rejecting the deal would create an “extremely complicated situation”, he added.

Johnson hopes for success in getting a fractious Parliament to back the deal after his predecessor, Theresa May, failed three times to get lawmakers behind her plan.

He said in The Sun newspaper on Saturday that a vote for the plan would bring a "painful chapter in our history" to an end.

He warned against further delay to Britain's departure from the European Union, telling lawmakers there was "little appetite" for another extension.

He told parliament that "further delay is pointless, expensive and deeply corrosive to public trust", as MPs sat on a weekend for the first time in 37 years to debate his divorce agreement.

As lawmakers gathered inside Parliament — their first Saturday sitting since the 1982 Falklands War — tens of thousands of anti-Brexit demonstrators were expected to march on the building, calling for a new referendum on whether to leave the EU or remain.

Saturday's vote could still be derailed.

Many lawmakers want to rule out the possibility that Britain could crash out of the bloc without a deal on the Oct. 31 deadline — a prospect economists say would disrupt trade and plunge the economy into recession.

A proposed amendment to Saturday's vote would withhold approval of the deal until all the necessary legislation to implement it has passed.

One of the lawmakers behind the measure, Oliver Letwin, said it would prevent the UK from leaving at the end of the month “by mistake if something goes wrong during the passage of the implementing legislation.”

If that amendment is chosen for a vote by House of Commons Speaker John Bercow and passes, Johnson will have to ask the EU for a delay to Britain's departure date.

Last month Parliament passed a law compelling the government to do that if no deal is approved by Saturday.

If the deal passes, Johnson is expected to introduce legislation on Monday to ratify the text, which must be pushed through before the end of the month.

A defeat would trigger a law requiring him to ask EU leaders to delay Brexit for what would be the third time. He has said he would “rather be dead in a ditch” than do so.

With inputs from PTI