Another constituency Labour Party is to debate affiliating to the pro-Jeremy Corbyn Jewish Voice For Labour group, just two days after another alarmed the Jewish Labour Movement by voting to do so.
The Hornsey and Wood Green CLP is the largest in the country and is to debate a motion on the JVL on Wednesday evening. The Harrow East CLP voted to affiliate to the group, which JLM called "extreme fringe voices" on Monday.
Joe Goldberg, the JLM's local government officer said a vote in favour of affiliation in Horsney and Wood Green could have "irreversible consequences".
Writing to JLM members in advance of Wednesday's meeting, he said: "If you, like me don't believe the JVL are any way near representative of our community, then join me in opposing the motion.
"Jewish Voice For Labour are extreme fringe voices. On Wednesday night our CLP will have a clear choice to make.
"As the largest CLP in the country it may well have irreversible consequences."
Last year, Mr Goldberg had quit his role on Haringey council suggesting it was "impossible to operate as a Jewish councillor... without having your views and actions prejudged or dismissed in terms that relate to your ethnicity.”
Jeremy Corbyn's office is said to have been made "fully aware" of the motion in Hornsey and Wood Green.
The Labour leader has insisted he recognises that JVL - which was founded as campaigning group for Palestinian rights who defended Mr Corbyn against alleged antisemitism 'smears' - did not represent mainstream Jewish opinion in the UK.
But there has been a move within Labour branches controlled by left-wing Momentum activists to press for affiliation to JVL instead of the JLM - which is repeatedly attacked for being pro-Zionist.
Last September, candidates backed by the left-wing Momentum group, won a string of key positions in the Hornsey and Wood Green CLP.
The JC revealed on Tuesday how left-wingers in the Harrow East CLP, which has a large Jewish population, voted to affiliate with JVL.