JEREMY Corbyn has got to change and adopt an internationally-recognised definition of anti-Semitism within the month, Gordon Brown has warned.

The former prime minister insisted the Labour Party has a problem with anti-Semitism which needs to be dealt with.

He said he was one of many within its ranks pushing for Mr Corbyn to address the issue urgently.

Mr Brown was speaking to a sold-out crowd at the Edinburgh International Book Festival, where he discussed his autobiography, My Life, Our Times.

Asked if he thought Mr Corbyn was a "fit and proper person" to be prime minister, Mr Brown failed to endorse him.

Instead, he 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 will change within a few weeks. I'm one of many people that's pressing for this change, and I believe that it will change.

"But even that will not be enough. You have got to show by your actions and not simply by saying some words that you understand the deep hurt that has been caused. I'm very clear about that."

He added: "I think people will have to make up their own minds. But in the immediate few days, this is what's going to happen. This can't keep going on as a running sore.

"It's not because it's an embarrassment. It is because it is simply wrong.

"The persecution that has been suffered by the Jewish community must never be forgotten.

"It's something that has got to be remembered every time we see vicious actions and discrimination and prejudice in different communities around the world."

Mr Corbyn has been heavily criticised over Labour's failure to accept the International Holocaust Remembrance Alliance (IHRA) definition of anti-Semitism in full.

It comes amid wider concerns over anti-Semitism within his party, with one of Mr Corbyn's own MPs accusing him of “supporting and defending” extremists.

He has also faced questions over his presence at an event which included the honouring of a Palestinian suspected of involvement in the 1972 Munich Olympics massacre, in which 11 Israeli athletes and coaches were murdered. Opponents have reported him to parliamentary bosses amid concerns the trip to the Palestinian martyrs' cemetery in Tunis was not declared.

Yesterday, a picture emerged of him apparently making a salute linked to an Islamist organisation found to have possible connections to extremism.

Mr Brown said there was "a problem within the Labour Party of anti-Semitism and it has got to be dealt with".

He continued: "I'm going to press hard that it be dealt with.

"Within a month, within a few days we have got to approve the international recommendations about how we deal with questions about the holocaust.

"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 anti-Semitism within our ranks."

Looking back over his time as Chancellor and later prime minister, Mr Brown admitted he failed to get through to the public during the 2008 financial crisis, and predicted the next economic upheaval would originate in Asia.

He said the quality of political debate was being hit by the internet, which he compared to a "shouting match without an umpire", full of intolerant and bigoted language.

The former MP called for a “new social consensus for the age of the gig economy” to rebuild trust in institutions.

A Labour source said the decision on whether to adopt the IHRA definition of anti-Semitism in full will be taken by the party’s ruling National Executive Committee, and not by Mr Corbyn.

A party spokesman said: “In recognition of the serious concerns expressed, Labour's NEC decided to re-open the development of the Code of Conduct, in consultation with Jewish community organisations and groups, in order to better address their concerns.

"Jeremy Corbyn has made it clear there is no place for antisemitism in the party, and that rooting it out and rebuilding trust and confidence among Jewish communities are priorities."