The Labour treasurer in Jeremy Corbyn's constituency has quit the party over its failure to deal with antisemitism.
Russell Smith-Becker, who was a member for 28 years and, said in his public resignation letter: “The Labour party has become somewhere antisemites feel comfortable and where many Jews feel uncomfortable.”
He was the treasurer for the Islington North Constituency Labour Party, where Mr Corbyn has been MP for 35 years.
Mr Smith-Becker's resignation comes after Labour’s refusal to adopt the International Holocaust Remembrance Alliance (IHRA) definition of Jew-hate, instead opting for its own code of conduct that omits key examples of how criticising Israel can by antisemitic.
Mr Smith-Becker posted his letter of resignation on Facebook. In it, he said he was "no longer sure that the Labour party is a force for good."
He said the decision to quit the party was "a real wrench" having joined it before he was old enough to vote.
Mr Smith-Becker said he had already written to Mr Corbyn about his concerns about antisemitism in the Labour party.
He wrote to the Labour leader after attending a protest in Parliament Square organised by the Lewish Leadership Council and the Board of Deputies of British Jews.
"When I encouraged you to listen to the JLC, BoD and other community groups I meant with a view to doing as they ask rather than the opposite," he wrote.
“When I encouraged you to take action on antisemitism I meant against it rather than to increase tolerance of it.”
Mr Smith-Becker said that he did not believe Mr Corbyn was an antisemite, but being “so often tolerant towards antisemitism has the same practical effect as if you were antisemitic.”
He defended veteran Jewish Labour MP Dame Margaret Hodge for branding Mr Corbyn an “antisemite and a racist” to the leader's face in the House Of Commons last week.
He wrote that it was “hardly surprising that people like Margaret Hodge might get the impression that you are."
Mr Smith-Becker added: "I am happy to support a party which is a force for good even if I have some differences, but I am no longer sure that the Labour party is a force for good.
"I therefore resign my leadership of the Labour party. The Labour party has become somewhere antisemites feel comfortable and where many Jews feel uncomfortable - I hope I can join again when it is the other way around."
A Labour spokesman said: "The Labour party is committed to eradicating antisemitism in all its forms.
"Labour’s new general secretary, Jennie Formby, has made it her first priority to speed up and strengthen our procedures and to develop a programme of political education to tackle antisemitism."
