FORMER Labour MP and Jeremy Corbyn critic John Woodcock has been challenged to call a by-election after quitting the party with a scathing attack on the opposition leader.

A spokesman for Corbyn accused the Barrow and Furness MP of deciding to “abandon” the party, after he called the Labour leader a “clear risk to UK national security as prime minister”.

Woodcock, 39, had been sitting as an independent since having the Labour whip withdrawn in April pending investigation of an allegation of sexual harassment.

In his resignation letter he said that, under Corbyn, Labour was no longer “the broad church it has historically been” and there was little chance of returning it to an “inclusive, mainstream electoral force”.

Speaking to reporters after PMQs, in which Woodcock asked a question regarding trains, a spokesman for Corbyn said: “In normal circumstances, if you stand for election on one platform and then decide to abandon the platform you stood on, basic rules of democratic accountability suggest that you should then put that to the electorate.”

Woodcock had a majority of 209 at the 2017 General Election.

He denies allegations over supposedly inappropriate texts and emails to a former female staff member between 2014 and 2016.

In his resignation letter, he dismissed the party’s disciplinary process against him as “rigged”.

He accused Labour general secretary Jennie Formby of overturning a previous disciplinary panel ruling and said Corbyn had refused to appoint an independent investigator to rule on his case.

And he said he had obtained emails showing that senior party figures were determined to prevent him standing in future elections as a Labour candidate because of his views on Corbyn’s leadership.

Woodcock said it was “not credible” for him to expect a fair hearing from Labour, and that he would now seek an independent process to hear the case.

His departure prompted a backlash from supporters of the Labour leader, with Unite general secretary Len McCluskey saying it was “no big deal”.

Corbyn’s spokesman insisted that the disciplinary process in Woodcock’s case was carried out in a “completely rigorous and fair” way.

But he said that Woodcock’s resignation meant that “the process cannot be pursued and accountability and recourse for the complainant can’t be achieved through Labour Party processes any more”.

Labour’s policy on sexual harassment cases states that cases are anonymised before being assessed by a panel of three members of the ruling National Executive Committee.

If this panel judges that there is a case to answer, they refer it to the disciplinary National Constitutional Committee, which is separate from the party leadership.