The opposition Labour party signal they will back a second referendum on Boris Johnson's Brexit deal.

Boris Johnson agreed on the terms of a withdrawal agreement with the EU on Thursday morning.

Jeremy Corbyn, Labour's leader, said Johnson's deal was "even worse" than Theresa May's, and added that "the best way to get Brexit sorted is to give the people the final say in a public vote."

Opinion polls consistently show that a majority of British people believe Brexit was a mistake.

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LONDON — Boris Johnson's hopes of taking Britain out of the EU on October 31 could be scuppered by the opposition Labour party, which is set to try and force a second referendum on the Brexit deal Johnson has agreed with the EU on Thursday.

Negotiators in Brussels agreed on the terms of a revised Brexit deal on Thursday after three days of intensive negotiations.

However, Jeremy Corbyn, Labour's leader, said Johnson's deal, which is set to be put before parliament on Saturday, appeared to be "even worse" than his predecessor Theresa May's, and said that "the best way to get Brexit sorted is to give the people the final say in a public vote."

It remains unclear whether the deal has enough support to pass through the Commons, which rejected his predecessor Theresa May's plan three times.

Many Labour MPs have said that they would only be willing to back the deal if it was attached to a confirmatory public vote, and plan to table an amendment to Saturday's vote, insisting that a deal will only be approved if it wins majority support in a referendum, which Labour appears increasingly likely to whip their MPs in favour of.

Labour's shadow Northern Ireland minister Lloyd Evans, said on Thursday — before the deal was announced — that the "best way through" was to "test public opinion" by holding a ballot which offers voters the choice to remain in the EU or to leave with a negotiated deal Boris Johnson brings back from Brussels.

Jeremy Corbyn had initially resisted the plan for a second referendum, insisting that the party's policy is to push for a general election instead.

But he appeared increasingly isolated this week, with several frontbenchers, including Shadow Chancellor John McDonnell and Brexit Secretary Keir Starmer, making it clear they would back a second referendum on Johnson's deal.

Rebel Conservative MPs could also make their support for a deal dependent on Johnson allowing a second referendum.

A majority of British people believe Britain was wrong to vote to leave the EU, according to long-running polling by YouGov.

Parliament is likely to approve the motion for an extraordinary weekend sitting later today.