She added: “Until today I had made no public comment about Jeremy’s ability to lead our party, but the fact that he failed to intervene is final proof for me that he is unfit to lead, and that a Labour Party under his stewardship cannot be a safe space for British Jews.”
Questioned after the meeting, Mr Wadsworth said he would not apologise.
He said he had been unaware that Ms Smeeth was Jewish, adding: "I am an ally of the Jewish people... I'm a whole-hearted supporter of fighting antisemitism and have been fighting against antisemitism and racism all my life and will continue to be… Jewish people have played a massive and crucial role in the anti-racism movement."
Ms Smeeth later tweeted that Ms Chakrabarti had apologised for her treatment at the press conference.
A previous version of this article reported that Marc Wadsworth had been accused of “abusing” a Jewish MP. Marc Wadsworth denies “abusing” the politician, and, instead, says that he challenged her during the launch event. We have amended the text and headline to reflect Mr Wadsworth’s position.