A  staunch ally of Jeremy Corbyn who quit the opposition frontbench this week, ‘should have been sacked long ago’ for his remarks about anti-Semitism according to a colleague.

Chris Williamson leaves his role as shadow fire and emergency services minister in what a source said was a “mutual decision” with the Labour leader Jeremy Corbyn to allow him to campaign on a broader range of issues.

However, Ilford North MP Wes Streeting said on Twitter that Williamson “should have been sacked long ago for his gross comments about anti-Semitism”.

In August, discussing rows over Mr Corbyn’s handling of anti-Semitism in the party, Mr Williamson told The Guardian: “Many people in the Jewish community are appalled by what they see as the weaponisation of anti-Semitism for political ends.

“It is pretty repellent to use that to attack somebody like Jeremy Corbyn, who has spent his whole life fighting for social justice and standing up for the underdog.”

Williamson, MP for Derby North, also said anti-Semitism allegations levelled at Corbyn were “bullsh*t” and “smears”.

At the time, Board of Deputies Vice President Marie van der Zyl  said: “The Jewish community would expect a Labour MP and shadow minister like Chris Williamson to show solidarity with those suffering racism within his own party rather than blaming the victims. After a second failure on equalities issues in a week, the Labour leadership should consider whether Williamson is a suitable person to serve as a front-bench spokesperson.”

Mr Williamson said: “I will be standing down from my role with immediate effect so that I can return to the backbenches, where I will be campaigning on a broader range of issues.

“I will continue to loyally support the leadership of Jeremy Corbyn from the backbenches and hope to be a voice for the party’s members.”