A senior Labour MP has used his exit from the Commons to criticise Jeremy Corbyn’s record as leader and blame the party’s current anti-Semitism crisis on him.

John Mann is set to stand down after 18 years in Parliament to take up the full-time post as the Government’s anti-Semitism tsar.

He said he could not campaign for Mr Corbyn knowing he could become prime minister, and told The Sunday Times he would “never forgive” his left-wing leader for allowing the party to be “hijacked” by anti-Semites.

Labour has ejected high-profile figures from the party, including former London mayor Ken Livingston and Corbynista MP Chris Williamson, after claims of anti-Semitism were lodged against them.

Jeremy Corbyn’s leadership of Labour has been condemned by one of his outgoing MPs Credit: PA

Luciana Berger, who quit the party in February and this week joined the Liberal Democrats, claimed Labour had become “institutionally anti-Semitic” since Mr Corbyn’s election as leader in 2015.

There have also been criticisms that Labour has been too slow to carry out investigations into complaints of anti-Semitism.

Mr Mann has reignited the debate after launching a tirade against Mr Corbyn in his parting shots.

The 59-year-old, who chairs the all-party parliamentary group against anti-Semitism, told the newspaper: “Corbyn has given the green light to the anti-Semites and, having done so, has sat there and done nothing to turn that round.

“Every time I go into a meeting with a group of Jewish people, I wince when they raise the issue of the Labour Party and Corbyn.

“It is impossible to overstate the anger that I have about that. He has not just hijacked my political party – he has hijacked its soul and its ethics. I will never forgive him for that.”

He has hijacked my political party's soul and its ethics. I will never forgive him for that

John Mann on Jeremy Corbyn

The Eurosceptic, who voted against opposition moves to block a no-deal Brexit on Tuesday, said he was “not prepared to lie” to voters, having admitted encouraging support for the party in the 2017 general election on the proviso that Mr Corbyn was unlikely to win.

“I can’t do that this time and I’m not prepared to lie to my voters. And neither am I prepared to tell them that Corbyn is appropriate to be prime minister. Because I don’t think he is,” he said.

Theresa May appointed Mr Mann her adviser on tackling anti-Semitism in one of her last acts as prime minister, but Boris Johnson has since upgraded the role, leading to Mr Mann opting to quit the Commons to focus all his efforts on the role – which will be based in the Ministry of Housing, Communities and Local Government.

The Labour Party has yet to respond to Mr Mann’s criticisms but in a reply earlier this year to questions on its handling of anti-Semitism complaints, a party spokesman said: “Labour is taking decisive action against anti-Semitism, doubling the number of staff dedicated to dealing with complaints and cases.”