The British government’s leading Brexit proponent says it is entirely possible another referendum on leaving the European Union could be held if Theresa May’s divorce deal is not voted through.

Michael Gove, the leading cabinet Brexiteer in Ms May’s Cabinet, told the BBC if MPs did not vote the proposed Brexit deal through on December 11, there may now be a Commons majority for another referendum.

The opposition Labour Party has said it will attempt to depose Ms May and force a general election if MPs reject her deal.

If that fails, they will then seek support in the House of Commons for another referendum.

Mr Gove said while Ms May’s Brexit was not perfect, “we have got to recognise that if we don’t vote for this, the alternatives are no deal or no Brexit”.

“There is a real risk if we don’t vote for this deal there may be a majority in the House of Commons for a second referendum,” he said

Ms May is battling to persuade sceptical British MPs to back the deal her government and the European Union reached last month.

Rejecting it would leave the UK facing a messy, economically damaging “no-deal” Brexit on March 29.

Labour Brexit spokesman Keir Starmer said it’s “inevitable” that Labour will bring a motion of no-confidence in the government if Parliament rejects the Brexit agreement.

“If she’s lost a vote of this significance after two years of negotiation, then it is right that there should be a general election,” Mr Starmer told Sky News.

If Ms May’s government lost a no-confidence vote, it would have two weeks to overturn the result with a new vote by MPs.

If that failed, Britain would hold a national election.

Politicians on both sides of Britain’s EU membership debate oppose the agreement May has struck with the bloc.

Brexiteers say it keeps Britain bound closely to the EU, and pro-EU politicians believe it erects barriers between the UK and its biggest trading partner.

With opposition parties and dozens of the Prime Minister’s fellow Conservatives against the deal, Ms May’s chances of winning the vote in parliament appear slim.

Labour is also trying to force May to publish confidential advice from the country’s top law officer about the Brexit deal.

Under opposition pressure, the government promised last month to show Parliament the legal advice “in full”, but now says the attorney general will make a statement to parliament.

Mr Starmer said Labour would accuse the government of being in contempt of parliament if it does not release all of the attorney general’s advice.

A key legal issue is how Britain can get out of a “backstop” provision that would keep the country in a customs union with the EU to guarantee an open border between the UK’s Northern Ireland and EU member Ireland.

Pro-Brexit MPs say the backstop could leave Britain tied to the EU indefinitely, unable to strike new trade deals around the world.

-with AAP