Ken Livingstone has withdrawn a legal challenge to the landmark equalities watchdog report into Labour antisemitism which claimed he had contributed to “unlawful harassment related to Jewish race and religion”.

The move was hailed by campaigners a “significant victory for the Jewish community” and a “humiliation” for the former London mayor.

The 2020 Equality Human Rights Commission (EHRC) report into Labour under Jeremy Corbyn found the party responsible for unlawful acts of harassment and discrimination.

Livingstone, 78, whose family announced this week has been diagnosed with Alzheimer’s disease, had been seeking a High Court review of the report along with Labour councillor Pat Bromley, both of whom were singled out in the 850-page document.

However, they accepted a deal offered by the EHRC that involves each side withdrawing from the case and bearing its own legal costs.

The EHRC legal costs are thought to have exceeded £215,000, while the Labour Party and the Campaign Against Antisemitism (CAA) also spent tens of thousands of pounds in legal fees.

An EHRC spokesperson said: “We firmly stand by our robust and fair investigation, the findings of which were accepted in full by the Labour Party.

“We welcome the decision to withdraw this judicial review claim, with disappointment at the valuable time and resources that we have had to expend on defending it.”

CAA chief executive Gideon Falter said: “This is a significant victory for the Jewish community, as it means that the EHRC’s groundbreaking report into antisemitism in the Labour Party stands.

“This is a humiliating end for Mr Livingstone and his co-complainant, and one that their supporters, whose funds were squandered, will surely question.

“We will continue our work to advocate for zero tolerance of antisemitism in all political parties, without fear or favour.”

The Jewish Labour Movement (JLM) also sought to intervene in the case but decided not to after receiving legal advice that Livingstone and Bromley’s case was weak.

Adam Langleben, a spokesman for the Jewish Labour Movement, said: “The [ECHR] document stands. The last…remote chance that the cranks had was this judicial review - and it's over.

“They lost, every time and everywhere they challenged it.”

In a statement, Livingstone and Bromley said: “We believe that, deep down, the EHRC understands that its investigation was flawed and that it acted unlawfully.

“That’s probably why they were willing to settle the case without recovering a penny of their exorbitant costs.”