Ian Austin has been a vocal critic of Labour leader Jeremy Corbyn and had pushed for a tighter anti-immigration stance.

A British legislator who quit the opposition Labour Party earlier this year saying it had been taken over by “extremists” and anti-Semites has urged voters to back Prime Minister Boris Johnson over Labour’s Jeremy Corbyn in next month’s election.

Ian Austin, who left Labour in February to stand as an independent member of Parliament, said Corbyn had failed to tackle anti-Semitism in the party and his left-wing economic policies would cost jobs and put investment at risk.

Furthermore, Labour’s Brexit policy of quickly renegotiating Britain’s European Union divorce deal and putting it to a new referendum was a “complete fantasy”.

“I’m not a Tory. This isn’t where I want to be,” Austin told BBC radio.

“I wouldn’t say that Boris Johnson is unfit to be our prime minister in a way that I say that about Jeremy Corbyn. I think the country has a big choice to make, and I think that Jeremy Corbyn is completely unfit to lead it.”

Labour’s deputy leader Tom Watson said on Wednesday he would stand down at the December 12 election but said the move was due to personal reasons, not the political differences he has had with Corbyn.

Austin, whose adoptive father was a Jewish refugee who fled the Nazis, said he could not accept what he said was the rise of anti-Semitism in Labour under Corbyn.

“Most shamefully of all for a party which has got a proud record of fighting for equality and opposing racism, the Labour Party has been poisoned with anti-Jewish racism under his leadership,” he said.

Labour has denied accusations of anti-Semitism since 2016, shortly after Corbyn – a veteran campaigner for Palestinian rights – became its leader. Labour said in July it was “implacably opposed to anti-Semitism”.