London: Britain's Labour party is entangled in a fresh row over Israel after it emerged that its leader, Jeremy Corbyn, has refused to attend an official dinner with the country's Prime Minister this week to mark the centenary of the Balfour Declaration, which helped to pave the way for a Jewish nation state.

The Labour leader's snub came as Israel's ambassador to London told The Sunday Times that those who oppose the historic declaration are "extremists" who reject Israel's right to exist and could be viewed on a par with terrorist groups such as Hamas.

The ambassador, Mark Regev, also suggested a "vocal minority" of British students and academics are still intent upon the destruction of Israel, 70 years after the country came into being.

Benjamin Netanyahu, the Israeli Prime Minister, has been invited to London by Theresa May to mark the Balfour centenary "with pride" on Thursday. However, Corbyn, a strong supporter of the Palestinian cause, has refused an invitation to a formal dinner that will take place in the evening. He has asked Emily Thornberry, the shadow foreign secretary, to attend in his place.

The move is reminiscent of last month's Labour Party conference in Brighton, where Corbyn avoided a Labour Friends of Israel reception attended by Regev. He sent Thornberry instead, claiming he had to work on his leader's speech - only to be spotted at three other receptions on the same night.

That snub came despite a row over left-wing activists at a conference fringe meeting calling for some Jewish groups to be expelled from Labour. It forced Corbyn to deny that he is in charge of "the nasty party".

Signed on November 2, 1917, by Arthur Balfour, Britain's then foreign secretary, the Balfour Declaration pledged the UK government's support for a Jewish "national home" in Palestine. The document is seen as a key staging post in the creation of Israel but has been criticised by Palestinians.

The Palestinian National Authority has described the declaration as "our tragedy" and has called on May to use this week's centenary to issue an apology, a move Downing Street has rejected.

Corbyn has previously called for an end to the "oppression" of the Palestinian people and, in line with official government policy, supports a two-state solution to the Middle East conflict.