Ash Sarkar clashed with a Labour MP as she ripped into Sir Keir Starmer over repeated U-turns.
The left-wing commentator said “you can’t trust” the Labour leader to stick to policies after he backtracked on pledges including £28 billion of green spending.
Labour MP Sir Chris Bryant insisted Sir Keir was “pragmatic” but Ms Sarkar hit back claiming it was a “nice way of saying liar”.
The fiery moment came as panellists on BBC Politics Live discussed whether a Labour government would “make a difference”.
Ms Sarkar said: “What Keir Starmer has shown is that he is willing to backtrack and scrap his pledges when he comes under even the most minuscule amount of pressure from the media.
“We saw that when it came to the £28 billion of green investment, that’s now been watered down to the point that much of it was already existing funding.
“He’s backtracked on tuition fees, he will potentially backtrack on this new package of workers’ rights, coming under pressure from Peter Mandelson there.
“So what that shows is that, well yes there might be these individual policies, you can’t trust him to keep them.”
Mr Bryant said: “He’s pragmatic, quite right too.”
But Ms Sarkar cut in: “That’s a nice way of saying liar.”
The Rhondda MP replied: “No, it’s not. We will not do what Liz Truss did which is make vast, uncosted plans and crash the UK economy.
“In relation to the £28 billion, completely right for us to change the policy because when we came up with the policy that was before Liz Truss crashed the economy, when borrowing was very cheap for government, now it’s very expensive.
“It would be utterly irresponsible for the Labour Party to go forward to a general election making uncosted promises that don’t add up.”
