David Triesman, a former Labour general secretary, Ara Darzi, an ex-health minister, and Leslie Turnberg all said they would no longer sit as Labour peers.
Lord Triesman accused Jeremy Corbyn and his inner circle of being “antisemitic” and said Labour was “no longer a safe political environment for Jewish people”.
The timing of their resignations will come as a blow to Mr Corbyn and his team ahead of the release of a BBC Panorama documentary on antisemitism in Labour, which is set to air on Wednesday night and expected to contain explosive new revelations.
In his resignation letter, Lord Triesman, who served as Labour’s general secretary from 2001 to 2013, said the party was “institutionally antisemitic”.
He said: “My sad conclusion is that the Labour Party is very plainly institutionally antisemitic, and its leader and his circle are antisemitic, having never once made the right judgement call about an issue reflecting deep prejudice. The number of examples is shocking.
“It is no longer a safe political environment for Jewish people or other opponents of antisemitism. It it time to recognise the reality. I always said it was worth hanging on to fight so long as there was a prospect of winning. I now don’t believe with this leadership there is.”
Lord Darzi, meanwhile, said his personal history was the driving force behind his decision. His family escaped the 1915 Armenian genocide.
He told the BBC’s Newsnight programme: “I confirm I am leaving the Labour whip to sit as an independent.
“As an Armenian survivor of the Armenian genocide I have zero tolerance to antisemitism, Islamophobia or any other discrimination against religion or race.
“This decision has not been lightly taken.”
Lord Turnberg also told the BBC that he was resigning the Labour whip.
In response to the resignations, a Labour spokesperson said: “We completely reject these false and offensive claims. The Labour Party at all levels is implacably opposed to antisemitism and is determined to root out this social cancer from our movement and society.
“Labour is taking decisive action against antisemitism, doubling the number of staff dedicated to dealing with complaints and cases. And since Jennie Formby became general secretary, the rate at which antisemitism cases have been dealt with has increased four-fold.
“Our records show that antisemitism cases that have gone through the stages of our disciplinary procedures since September 2015 account for about 0.06 per cent of the party’s membership. This represents a tiny minority, but one antisemite is one too many, and we will continue to act against this repugnant form of racism.”
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