General secretary Jennie Formby has re-suspended Chris Williamson  from the parliamentary party following a backlash from MPs, members and Jewish groups.

The move comes only two days after the Labour MP was readmitted to the party in a vote by a three-person panel from Labour’s National Executive Committee.

Ms Formy took the decision after several key members of the Labour's National Executive Committee  agreed privately they would refer Mr Williamson for full investigation next month.

A group of 60 Labour MPs increased the pressure on the the party's ruling committee earlier today when they wrote to the chair of the Parliamentary Labour Party (PLP) in an attempt to use a loophole to re-suspend the party whip from Mr Williamson.

The MPs, including members of the Shadow Cabinet, signed the letter sent to John Cryer, according to Sky News political correspondent Tom Rayner.

The letter asked the Parliamentary Committee at its meeting next Wednesday to “consider an application to withdraw the whip” from the Derby North MP.

Mr Williamson was suspended from Labour in February after suggesting that the party had been “too apologetic” regarding antisemitism, one of many statements which had angered British Jews.

The step from the PLP to suspend the whip from Corbyn had been mentioned on Thursday by Jacqui Smith, the former Labour Home Secretary, as a possible way of exclusing Mr Williamson. 

Friday’s letter, written by Diana Johnson, MP for Kingston upon Hull North, noted a standing order of the PLP which would allow MPs to suspend the whip of a fellow Labour MP.

“We are of the view that the allegation of bringing the Labour Party into disrepute made against Chris Williamson warrants an investigation by the Parliamentary Committee under this standing order,” the letter reads.

“We therefore seek to ask the PLP to take action to suspend the whip from Chris Williamson for a period of a year.”

According to Mr Rayner, Keir Starmer, shadow secretary of state for exiting the European Union, will also be asking the Equality and Human Rights Commission (EHRC) which is investigating accusations of institutionalised antisemitism in Labour, to look at the NEC decision to readmit Mr Williamson as part of their wider investigation.

On Thursday, despite letters from MPs, peers and party staffers urging Jeremy Corbyn, the Labour leader, to take action, he declined to get involved, responding, when asked about it, that the NEC panel "went though the case in great detail and...made that decision".

Mr Williamson has been one of Mr Corbyn’s most vocal allies among Labour MPs. Mr Corbyn publicly defended him a few weeks prior to his suspension, telling the Derby Telegraph, Mr Williamson’s hometown paper, that the MP was “a strong anti-racist campaigner”.

During Mr Williamson’s suspension, Mr Corbyn continued to maintain a close relationship with the MP, on one occasion in the House of Commons chamber putting his arm around him and describing him as a “comrade”.

Even if MPs do not get the opportunity to vote to withdraw the whip from Mr Williamson, there are increasing indications that the MP will soon find himself once again suspended from the party. According to the Huffington Post, when the NEC next meets in full on Tuesday July 9, the organisation's Disputes Panel will seek to reject the earlier decision of the three-person panel, after which the 33-person NEC organisation sub-committee will vote on whether to reopen the disciplinary procedure against Mr Williamson and refer the case to the NCC (National Constitutional Council), the party's highest committee and the only one with the authority to expel members.