The damning report into anti-Semitism under Jeremy Corbyn gave Sir Keir Starmer enough wiggle-room not to further enflame party tensions by taking immediate action against his predecessor.

But Mr Corbyn’s refusal to fully accept the Equality and Human Rights Commission’s findings and his insistence that the extent of racism in the party had been “dramatically overstated for political reasons” forced Labour’s hand.

After failing to retract the comments in a subsequent interview despite a clear warning from Sir Keir, the veteran MP – who until April had led the party – was suspended pending an investigation.

The human rights watchdog’s report is scathing, finding three breaches of equalities law and evidence of “political interference” in the complaints process by then leader Mr Corbyn’s office, while criticising “serious failings in leadership”.

It did not go as far as identifying Mr Corbyn as the sole problem, with the EHRC saying the issue went beyond his role and across the party under his tenure.

Just before Sir Keir held a press conference to apologise during what he said was a “day of shame” for Labour, the Islington North MP released his own statement.

Mr Corbyn acknowledged “one anti-Semite is one too many”, but claimed the “scale of the problem was also dramatically overstated for political reasons by our opponents inside and outside the party, as well as by much of the media”.

While he said he trusts the report’s recommendations will be implemented “to help move on from this period”, he added: “I do not accept all of its findings.”

Minutes later Sir Keir, in front of a podium with the slogan “a new leadership”, was seemingly unaware of Mr Corbyn’s remarks.

Sir Keir said: “If – after all the pain, all the grief, and all the evidence in this report – there are still those who think there’s no problem with anti-Semitism in the Labour Party, that it’s all exaggerated, or a factional attack, then, frankly, you are part of the problem too.

“And you should be nowhere near the Labour Party either.”

The two statements clearly put the men at odds, but it was not until a subsequent refusal by Mr Corbyn to back down on the remarks in an interview that his suspension was sealed.

Mr Corbyn denied any political interference in the complaints process doing a pooled interview, and doubled down on his assertion that the extent of the problem had been overstated.

Moments later, a Labour spokesman said: “In light of his comments made today and his failure to retract them subsequently, the Labour Party has suspended Jeremy Corbyn pending investigation.

“He has also had the whip removed from the Parliamentary Labour Party.”

The suspension, said to have been an order from party HQ and not Sir Keir himself, came as a huge blow to the Labour stalwart, who had earlier said he “of course” would not resign from the party he joined aged 16.

He tweeted: “I will strongly contest the political intervention to suspend me.

“I’ve made absolutely clear those who deny there has been an anti-Semitism problem in the Labour Party are wrong.

“I will continue to support a zero-tolerance policy towards all forms of racism.”

His suspension was welcomed by Marie van der Zyl, president of the Board of Deputies of British Jews.

She said: “Having presided over the descent of a proudly anti-racist party into a party that broke equalities law in its treatment of Jews, his shameless comments today showed that he remains part of the problem and is an obstruction to the resolution of the issue.”

But while Jewish groups supported the move, the suspension of the veteran activist and stalwart of the Labour left is bound to reignite the party’s persistent divisions.