Many of the UK's approximately 300,000 Jewish citizens were questioning whether it was safe to raise children in the country, Britain's former Chief Rabbi Jonathan Sacks said on Sunday.

Sacks, an independent member of the UK parliament's upper house, said the opposition Labour Party leader Jeremy Corbyn, in particular, must "recant and repent" and said he risked engulfing the country "in the flames of hatred."

Corbyn has been accused of dragging his feet on unequivocal support for an internationally recognized definition of anti-Semitism and of failing to acknowledge the depth of the problem in the center-left party, which has traditionally been sympathetic towards the plight of the Palestinians in Israel.

"Corbyn poses a danger as prime minister unless he expresses clear remorse for past statements," Sacks said in a BBC interview.

The EU Commission President Jose Manuel Barroso (center) and UK chief rabbi Sir Jonathan Sacks

"When people hear the kind of language that has been coming out of Labour, that's been brought to the surface among Jeremy Corbyn's earlier speeches, they cannot but feel an existential threat," Sacks went on.

Read more: Opinion: Separating anti-semitism from criticism of Israel

Corbyn has said anti-Semitism has no place in the Labour Party, but it remains uncertain if the party's executive committee meeting this week to discuss its definition of anti-semitism will endorse the International Holocaust Remembrance Alliance (IHRA) definition in Labour's new code of conduct.

The IHRA has been signed by 31 countries and is used by many British institutions.

The Labour leadership has argued the definition does not allow for full criticism of Israel's treatment of Palestinians.

Protests organized by the British Board of Jewish Deputies opposing anti-Semitism, in London in March

Calls for an apology

Ex-PM and Labour leader Gordon Brown on Sunday called on Labour to endorse the IHRA.

"It is needed now to deal with practical threats, to confront gathering dangers and on-the-ground realities of very real, week-by-week threats to Jewish communities that demand an unequivocal response and unqualified resolve," Brown told the Jewish Labour Movement conference.

Read more: Anti-Semitism on the rise? Western European Jews think so

Brown, prime minister between 2007 and 2010, said the issue touched at "the soul of the Labour Party."

"This is a problem that is real and present and something that's got to be dealt with now," he said.

"I want to say to you very clearly today that the IHRA definition of anti-semitism is something we should support unanimously, unequivocally and immediately," Brown went on. "Jews have been in Britain since 1656, I know of no other occasion in these 362 years when Jews ... are asking 'is this country safe to bring up our children'," he told the BBC.

Leading Jewish organizations called on Corbyn to end the row last week. The Board of Deputies of British Jews, the Jewish Leadership Council (JLC) and the Community Security Trust (CST) wrote letters to Labour's general secretary before Labour's ruling executive committee meets on Tuesday.

jbh/rc (AFP, AP)

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