The Labour leader said his predecessor – stripped of the party whip in 2020 – “won’t stand as a Labour MP at the next election or any election”.
It came as hundreds of pro-Palestine protesters gathered outside Sir Keir’s office in north London on Saturday demanding that he back a ceasefire and chanting: “Keir Starmer’s a wasteman”.
Mr Corbyn had been repeatedly asked on Talk TV’s Piers Morgan Uncensored programme this week if he thought Hamas was a terror group. But the independent Islington North MP, an outspoken critic of Israel, continually avoided the question.
Mr Corbyn has now described Hamas as “a terrorist group” in a new article for Tribune – but also accused the Israeli army of being guilty of “acts of terror too”.
Sir Keir – who served in Mr Corbyn’s shadow cabinet – said he was “taken aback and shocked” by the left-wing stalwart’s refusal to describe Hamas as a terror outfit in the TalkTV interview.
“It reaffirmed in me why it is so important to me and to this changed Labour Party that Jeremy Corbyn does not sit as a Labour MP and will not be a candidate at the next election for the Labour Party,” he told the News Agent podcast. “That is how far we have changed as the Labour Party.”
Asked whether Mr Corbyn’s interview with Piers Morgan would preclude him from standing for Labour again, Sir Keir: “He won’t stand as a Labour MP at the next election or any election. His days as a Labour MP are over. We have a changed party.”
In an article for the left-wing Tribune magazine, Mr Corbyn wrote that “I deplore the targeting of all civilians”, including Hamas’s killing of around 1,200 people in Israel – but went on to accuse the Israeli army of “acts of terror”.
“If we understand terrorism to describe the indiscriminate killing of civilians, in breach of international law, then of course Hamas is a terrorist group,” the former Labour leader wrote.
He added: “The targeting of hospitals, refugee camps and so-called safe zones by the Israeli army are acts of terror too; and the killing of more than 11,000 people, half of whom are children, cannot possibly be understood as acts of self-defence.”
Mr Corbyn had the Labour whip in parliament removed in October 2020 over his response to the equalities watchdog report on antisemitism in the party during his tenure as leader. He sits as an independent MP but remains a Labour member.
Sir Keir faced a bruising week on the issue of the Israel-Hamas war, suffering a major rebellion in the Commons against the party’s position of refusing to back a ceasefire.
Pro-Palestine crowds blocked the road outside his Camden office on Saturday and chanted: “Keir Starmer’s a wasteman” and “What do we want? A ceasefire. When do we want it? Now.”
The opposition leader said he was “not daunted” by the prospect of entering No 10 if Labour wins next year’s general election – but revealed that he has worried about his family’s safety.
He said: “I’ve got two children: I’ve got a 15-year-old boy and a 12-year-old girl. And my biggest concern – about the only concern I have going forward – is asking myself over and over again, particularly at the moment, how do I protect them as we go into this?”
The Labour leader – who has backed Rishi Sunak’s call for a “humanitarian pause” – had put his MPs on a three-line whip not to vote for an SNP motion calling for an immediate ceasefire.
But 56 of his MPs defied the order, 10 shadow ministers and parliamentary aides among them. The frontbenchers, including Jess Phillips, quit or were sacked as a result.
Sir Keir insisted that there is “no unconditional support for Israel” as it fights back against Hamas, and urged that civilians and hospitals “must be protected” and international law upheld.
Labour rebels could still join Sir Keir’s top team after the election, the shadow defence secretary John Healey said.
Asked whether their stance would rule them out of a ministerial post in a Labour government, Mr Healey said: “That’s for well down the track,” before insisting there was a “deeper unity” in the Labour Party.
Other former shadow ministers now on the back benches include Yasmin Qureshi, Afzal Khan, Paula Barker, Rachel Hopkins, Sarah Owen, Naz Shah and Andy Slaughter. Parliamentary private secretaries Dan Carden and Mary Foy joined them in stepping down.
Saturday saw pro-Palestine protest organisers oversee a national day of action, instead of a large march in central London.
The direct action took the form of more than 100 smaller rallies at various locations across the UK. Previous weekends have seen thousands of protesters and counterprotesters converging on the capital.