Ex-UK Labour staffers are preparing to expose 100,000 emails that show Jeremy Corbyn’s team protected those accused of antisemitism.

They will include “tens of thousands” of examples of how the party ignored complaints that supporters were promoting Jew-hate, as well as sworn affidavits describing the attempts to protect those who were seen as loyal to Corbyn.

One former staffer told : “The protection of antisemites was on a scale and at a level the public does not begin to understand.”

In March the Equality and Human Rights Commission [EHRC] began pre-enforcement proceedings against Labour, after the party was reported to the body for its failure to take proper action against antisemitism among its members.

The EHRC is due to meet after the European elections to decide whether to make its investigation statutory.

Insiders at the organisation were saying the evidence they had already received “meets the legal threshold for a statutory investigation.”

This would override any non-disclosure agreement which Labour HQ made staffers sign on their departure.

One former Labour staffer told that “everyone is going to speak out”, saying they had saved the incriminating evidence before leaving both because they were disgusted by the racism and in case the party attempted to threaten them in future.

The evidence gathered by the ex-Labour staffers shows successful efforts by Jeremy Corbyn’s chief of staff, Karie Murphy to prevent the Labour leader’s supporters from being expelled from the party over their comments.

Jon Lansman, Momentum’s Jewish founder, said that he was “deeply shocked” by “evidence…that former Labour party staff who are still Labour members may have deliberately delayed action on antisemitism”.

Peter Mason, national secretary of the Jewish Labour Movement, replied: “Funny that, Jon, because I’m deeply shocked by evidence that senior staff and NEC members have deliberately intervened in action against antisemites”.

“Good luck getting an investigation. [JLM] asked for years and didn’t get one. So we’ve asked EHRC to do it instead.”