Gordon Brown has said Jeremy Corbyn needs to make changes in response to concerns about antisemitism in the Labour party.

The former prime minister said the issue was a “running sore” that should be dealt with immediately

During an appearance at the Edinburgh international book festival, Brown was asked whether he thought Corbyn was a fit and proper candidate to be prime minister.

Corbyn and the Labour party have been engulfed in controversy after failing to endorse the International Holocaust Remembrance Alliance’s (IHRA) definition of antisemitism in its entirety. Corbyn has also been criticised for attending an event at a Palestinian cemetery in Tunisia in 2014.

Brown said: “Jeremy Corbyn has got to change. He cannot sustain particularly what he is saying about the international agreement on what we do in our attitudes to both the Holocaust and to Israel. I predict to you that’s going to change within a few weeks. I believe that it will change but even that will not be enough.

“You have got to show by your actions, not simply by saying some words, that you understand the deep hurt that has been caused. I’m very clear about that.”

He added: “We have a problem in Britain, not just with Islamophobia and not just with racism against the black community. We have a problem within the Labour party with antisemitism and it has got to be dealt with.

“Within a month, within a few days, we have to approve the international recommendations about how we deal with questions about the Holocaust and it’s absolutely central to the progress of a democratic society that is tolerant and liberal that a party like the Labour party comes out strongly against any antisemitism within the far right.”

He said he would not predict what would happen in the Labour party but the issue had to be sorted out immediately.

“This cannot keep going on as a running sore, and it’s not because it’s an embarrassment, it is because it is simply wrong,” Brown said.

“The persecution that has been suffered by the Jewish community must never be forgotten. It is something that has got to be remembered every time we see vicious actions and discrimination and prejudice in different communities around the world.”