Sir Tony Blair has warned Andy Burnham not to enter a coalition with the Greens after the party was widely condemned for voting to adopt a policydefining Zionism as racism.

The former Labour prime minister hit out at Zack Polanski’s party, accusing it of crossing “a dangerous line”.

The move effectively “branded the majority of the (UK’s) Jews racists” at the same time as the Greens “harm the Palestinian cause—the very cause they say they support,” he said.

“There are those in my party, Labour, who might be tempted by the so-called progressive Red-Green coalition—an alliance between Labour and the Greens to unite the British left. But this vote should serve as a warning of the dangers such an alliance would bring,” he wrote in the American website The Free Press.

But the ex-PM is the most prominent Labour figure to publicly make the call.

Chief rabbi Sir Ephraim Mirvis has said that the motion, passed at Greens’ annual conference at the weekend, is a “threat to British Jews and to Britain”.

The chair of Amnesty International, Sandy Ruthven, left the party, telling the Jewish Chronicle it was “failing to confront prejudice” in its ranks.

Israel also accused the Greens of legitimising “the destruction of the state of Israel” with a “clear antisemitic text”.

Mr Polanski, who did not vote, has been barred from entering Israel in response to the motion.

Read More: Blair warns Burnham Labour should not do coalition with the Greens: ‘They’ve crossed a line’