Senior Labour Party figures say Brexit talks with the government are still a long way finding an agreement.

Shadow Chancellor John McDonnell said that the government's offer was "nowhere near" what Labour wanted.

He added that Conservative party infighting was making it harder for Labour to sign up to a deal: "Let's be absolutely straight, today hasn't helped."

Theresa May and her Cabinet agreed to continue Brexit talks with Labour on Monday.

LONDON — Talks between Theresa May's government and the opposition Labour Party to find a compromise Brexit deal have hit a new low according to the Shadow Chancellor John McDonnell.

Speaking at an event hosted by the Wall Street Journal on Tuesday, Labour's Shadow Chancellor McDonnell said that the government was "nowhere near" to accepting Labour's demand of a permanent customs union with the European Union.

"We have been at this five weeks. We haven't seen the significant shift yet that we require to support a deal," McDonnell said.

"We want a permanent, comprehensive customs union. We want dynamic alignment with the single market. We want protection of worker, consumer and environmental rights."

He added: "The customs union element is absolutely key to us.

"I won't go into the detail of what's been offered but it's nowhere near enough."

McDonnell's comments were echoed by Labour's Shadow Environment Secretary, Sue Hayman.

She told Business Insider on Tuesday that Labour was "trying to be very constructive" in talks with government ministers "but for there to be genuine progress the government has to move on its red lines."

She suggested that Labour could soon walk out of talks if the government did not shift its red lines.

"At the moment we are committed to continuing them but we need to be able to get to a stage where we believe that any deal we come up with is something we can through Parliament — and that isn't straightforward."

McDonnell said that talks had hit a particularly low point on Monday after senior Tory MPs, including possible successors to May, wrote to the prime minister urging her not to strike deal with Labour based on a customs union.

The letter, signed by former 13 former Cabinet ministers including leadership frontrunners Boris Johnson and Dominic Raab, warned May that a deal based on Labour's core demand would be "bad policy and bad politics."

McDonnell said "let's be absolutely straight, today hasn't helped," adding that it meant any deal agreed between the government and Labour could be ripped up by whoever replaces May as prime minister.

"It gives us no security and we expect a response from the government."

He added: "If we are going to march our troops in parliament to the top of the hill to vote for a deal, and then that's overturned in weeks, I think that would be a cataclysmic act of bad faith."

McDonnell's comments came as May's Cabinet met on Tuesday morning to discuss the progress of talks.

A spokesman for the prime minister said there had been an "extensive" discussion on possible compromises with Labour, but that no conclusions had been reached.

He added that the Cabinet had agreed to continue talks, but said that it was "imperative" that they must be concluded soon in order to allow Brexit legislation to pass through parliament before the start of the summer recess - currently scheduled for late July.

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