Rhea Wolfson's attempt to replace Ken Livingstone on Labour’s Na tional Executive Committee has been blocked.

The Jewish Labour activist was attempting to fill the vacancy left by Ken Livingstone after he was suspended from the party for claiming that Hitler backed Zionism.

Her bid was endorsed by Momentum, a hard-left group loyal to Jeremy Corbyn.

However, she had to abandon it after Jim Murphy, former leader of the Scottish Labour Party, called on her Constituency Labour Party to reject her nomination at a meeting on Tuesday.

In a statement posted on Facebook, Ms Wolfson, former president of Oxford University’s Jewish and Israel societies, and ex-chair of the Zionist Youth Council, claimed that Mr Murphy had argued that “it would not be appropriate to nominate me due to my endorsement by Momentum, which he claimed has a problem with antisemitism.

“The CLP then voted to not endorse me.”

She added that the decision was disappointing “because I am the only Jewish candidate in this election, because the wide range of organisations endorsing me includes the Jewish Labour Movement, and because I have a long record of challenging antisemitism.”

Meanwhile Momentum cancelled a debate on antisemitism after complaints that it clashed with Shabbat — and then held it anyway.

The event, organised by Momentum’s Haringey branch in north London, had been called off after Jewish Labour supporters said the Friday night scheduling was “crass and insensitive”.

But the meeting went ahead at the same venue in Tottenham, north London, with attendees being told that it “was not an official Momentum event”. The speakers in cluded Jacqueline Walker, whose suspension from Labour for accusing Jews of being “chief financiers of the sugar and slave trade” has been lifted.

Mr Corbyn has been criticised for failing to reply to an invitation sent in April from the Labour Party in Israel inviting him to the Yad Vashem Holocaust museum in Jerusalem.

Wes Streeting, Labour MP for Ilford North, said the leader’s failure to respond was “fairly typical of the flatfooted and lackadaisical attitude that we’ve seen from the outset. It is simply unaccept able.”

Ken Livingstone’s show on LBC has been dropped in the wake of the controversy surrounding his comment that Hitler backed Zionism. A spokesman for the radio station confirmed that Mr Livingstone would no longer be present ing the Saturday politics show.

Luke Cresswell, who has served as chair of the South Suffolk Con stituency Labour Party, has been suspended.

In a Twitter post last month he shared a post with a picture of an Israeli flag alongside the message: “God did not give you the land — the UK did illegally”.

Jewish academic David Hirsh has resigned from the Jews for Justice for Palestinians group, accusing it of being “more part of the problem than part of the solution” to an tisemitism on the British left.