Ahead of voting in the House of Commons on Wednesday, Amber Rudd, David Gauke and Greg Clark, three British cabinet ministers, have warned publicly for the first time that they would vote to give Britain more time to negotiate a deal with the European Union, going against Theresa May and breaking cabinet unity.

Number 10 said in a statement: "The PM is working hard to ensure we get a deal with the EU that allows us to deliver on the result of the referendum. ...That is where the cabinet's energy should be focused."

MPs are due to debate Brexit again next Wednesday and are expected to consider an amendment tabled by former Tory minister Sir Oliver Letwin and Labour's Yvette Cooper to give Parliament the opportunity to delay Brexit and prevent a no-deal situation if there is no agreement with the EU by the middle of March.

British opposition leader Jeremy Corbyn said if his party won power he would renegotiate a Brexit deal with the European Union and could hold another referendum, as he comes under pressure to support giving the public another chance to stay in the bloc.

Parliament is deadlocked over Britain's departure from the European Union after resoundingly rejecting Prime Minister Theresa May's plan last month, throwing up several outcomes, including leaving without a deal or a second referendum.

Corbyn, when asked if he would hold a referendum on any deal on any deal he negotiated, told Sky News: "We'd consider putting that to the public."

Asked to clarify if he was considering calling for another referendum, Corbyn said: "That's the point we're discussing now in the party."

This comes after nine Labour lawmakers quit the party this week over its approach to Brexit and anti-Semitism.

Earlier John McDonnell, the second most powerful man in the Labour Party, gave his strongest indication yet that Labour is close to backing a second public vote and said he would campaign for remain if one is held.

McDonnell said Labour is "moving towards" a second referendum on Brexit. He said an amendment calling for a public vote which is being tabled for debate next week by lawmakers "could be a solution."

The party's would-be finance minister said that any referendum would have remained in the European Union as the alternative to the deal.

"If we were going on a People's Vote based on a deal that has gone through parliament in some form, if that got voted down then you'd have status quo, and that would be remain," he told the Evening Standard.

"I'd campaign for remain and I'd vote for remain."

May has ruled out staging a second vote, saying parliament should respect the 2016 referendum when 52 percent of Britons who cast a vote chose to leave the EU. But supporters of a second referendum say it is the only way to break the deadlock in parliament by asking for the people to decide.

May's spokeswoman said that the PM would have another "period of engagement" on Brexit at an EU-League of Arab States summit in Sharm el-Sheikh, Egypt - including a meeting with European Council president Donald Tusk in the coming days.

(With inputs from Reuters)