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Theresa May's offer to bring Jeremy Corbyn into Brexit talks hasn't gone down well with the Brexit hardliners in her own party.

Conservative Member of Parliament Jacob Rees-Mogg, chairman of the European Research Group, a pro-Brexit bloc, said May had made the wrong move.

"This approach to government is an unsuccessful one and it also lacks democratic legitimacy," Mogg said in response to May's speech, according to the Press Association. "People did not vote for a Corbyn-May coalition government – they voted for a Conservative government, which became a confidence and supply with the DUP," he said, referring to the small Northern Irish party that notionally props up May's administration.

He added:

"This is a deeply unsatisfactory approach ... It's not in the interests of the country, it fails to deliver on the referendum result and history doesn't bode well for it."

Rees-Mogg said he was resolutely opposed to May's offer of talks with the opposition. "I think getting the support of a known Marxist is not likely to instill confidence in Conservatives," he added. (Jeremy Corbyn's politics sit to the far left of the Labour Party.)

Former Foreign Secretary Boris Johnson, meanwhile, expressed his anger with the strategy on Twitter. "It is very disappointing that the cabinet has decided to entrust the final handling of Brexit to Jeremy Corbyn and the Labour Party," he wrote.

"We now face the ridiculous possibility of being forced to contest the European elections more than three years after leaving the EU and having to agree to exit terms that in no way resemble what the people were promised when they voted to leave," he added.