Sir Keir Starmer said the issue of depriving Diane Abbott of the Labour whip has not been “resolved” as he resisted calls to welcome her back into the party fold.
Ms Abbott, who is at the centre of a racism row, has asked the Labour leader to restore her to his party’s parliamentary ranks.
Britain’s longest-serving black MP was the target of comments by Tory donor Frank Hester, who allegedly said in 2019 that she made him “want to hate all black women” and that she “should be shot”.
Sir Keir said “we must support” Ms Abbott after the recent emergence of Mr Hester’s “racist and misogynistic” remarks.
However, he said that should not be conflated with the antisemitism accusations she faces over a letter she wrote to The Observer suggesting Jewish, Irish and Traveller people are not subject to racism “all their lives”.
Ms Abbott, first elected as MP for Hackney North and Stoke Newington in 1987, has sat as an independent MP since April after the Labour whip was withdrawn following her letter to the newspaper.
Following a backlash, she apologised for any “anguish” caused and withdrew her comments.
After Wednesday’s Prime Minister’s Questions, in which Sir Keir urged Rishi Sunak to return Mr Hester’s £10 million donations, the Labour leader approached Ms Abbott to offer support.
Ms Abbott, who remains a Labour member, said she replied: “You could restore the whip.”
But on Thursday, Sir Keir said the suspension was “an entirely different issue” from the racism storm and cautioned against conflating the two matters.
“That was about allegations of antisemitism in relation to a letter… which is subject to an ongoing investigation, which is separate from me. That’s not something which I conduct,” he told the BBC’s Jeremy Vine.
He said the “independent process” was “not resolved”.
Sir Keir also noted that Ms Abbott has been “subjected to more of that kind of abuse than I think any other MP ever”.
“We absolutely need to put our arm around her and give her support in relation to that,” he added.