Len McCluskey has claimed his Unite union has voted to cut funding for the Labour Party because of “anger”at Sir Keir Starmer’s decision to pay damages to the Panorama antisemitism whistleblowers.

Unite’s general secretary said the union’s executive council had voted to reduce its affiliation to Labour by 50, 000 members, which would cut the amount it donated to the party by 10 per cent.

Labour received £7 million from the union last year – but in an attack on Sir Keir’s leadership, Mr McCluskey said he no longer knew what “Labour stand for”.

Asked by BBC Newsnight why the union’s executive were so angry with the new leader, he said it was “because they thought it was an absolute mistake and wrong to pay out huge sums of money to individuals who were suing the Labour Party based on the Panorama programme, when Labour’s own legal people were saying that they would lose that case if it went to court”.

He added: “So we shouldn’t have paid them anything.”

The JC has revealed how eight former staffers last year sued the party for defamation, saying senior Labour figures had issued statements attacking their reputations and suggesting they had ulterior political and personal motives to undermine the party.

When the programme was broadcast, a Labour spokesman called them “disaffected former officials” and said they had “worked actively to undermine” Jeremy Corbyn and had “both personal and political axes to grind”.

After the settlement of the Panorama libel cases was announced in August, Mr McCluskey said there was “no doubt” the union’s executive would review its contributions to Labour.

While the loss of union funding will come as a blow to Labour, there has been a significant return of private backing for the party following the exit of Mr Corbyn, including from a number of Jewish donors.