Karl Turner is still waiting to hear an update on his suspension after Andy Burnham restored the whip to both Diane Abbott and Joani Reid

Suspended Labour MP Karl Turner has threatened to sue Business Secretary Jonathan Reynolds amid allegations of disability discrimination when he was smeared as mentally ill.

Mr Turner, who supported Andy Burnham replacing Sir Keir Starmer as Prime Minister, had the Labour whip withdrawn after lambasting David Lammy's proposed reforms to jury trials.

The Kingston upon Hull East MP is accusing senior figures inside the Labour Party of weaponising his past mental health struggles and now demanding a six-figure payout.

Mr Reynolds, who served as Sir Keir's Chief Whip despite allegations he embellished his CV, will be listed as a separate defendant to the Labour Party.

The Business Secretary denies the claims made against him by Mr Turner.

"Labour takes seriously its duties of care towards all its elected representatives as well as its legal duties," a Labour source said.

However, Mr Turner repeated his claim in a direct plea to Sir Keir at Prime Minister's Questions on May 20.

He said: "I received hostile briefings and smears about my mental health from the lads in No10, Downing Street.

"The Chief Whip is shaking his head, but he knows about it. The Prime Minister knows that my nephew Matty took his own life as a result of work-related stress as a young criminal lawyer.

"During Mental Health Awareness Week, when ministers spoke with compassion about health and wellbeing, did the Prime Minister reflect on those hostile, discriminatory briefings, which he knew about and allowed to happen?"

The Prime Minister replied: "I totally understand that, and I want to be absolutely clear that nobody should be smeared in relation to mental health—nobody—on any issue, whatever they may argue on any other issue.

"I will do everything I can to make sure that that is the position."

Mr Turner is currently in talks with Mr Burnham and current Chief Whip Anneliese Midgley over his potential return to the Labour benches.

However, a Government source suggested Mr Turner will only have the whip restored if he apologises to Mr Reynolds.

“Anneliese will want every Labour MP back on the pitch as a Labour MP," the source told The Times.

"But for Karl, he is going to need to have a conversation about why he was suspended and will need to resolve some of those issues."

Mr Turner's decision to take Labour to an employment tribunal also appears beyond the scope of current law, with the party not currently considered an official employer.

However, the 55-year-old is hoping to claim the parliamentary party is an "association" under the banner of a registered political party.

Mr Turner could transform the way MPs and political parties interact if he secures victory.

But Mr Burnham is also looking to change the relationship between Labour MPs and the Chief Whip.

He said: “I look back at the times when I was in the PLP [Parliamentary Labour Party] … if we’d gone with what the PLP was saying — and I am talking about Iraq, but I’m talking about other things as well — the conscience of the PLP will guide the Government, that’s what I believe.”

The Prime Minister added: “Where it goes wrong is if a small group of people at the top use the whip as an instrument of threat.

"I think the Government will be better served by the collective wisdom of the PLP, personally … the main thing I would come to is authenticity.

"Let your representatives be authentic representatives of their places.

"Don’t punish them for taking a position that actually connects with people they are serving. Don’t send them into TV studios with lines to take on everything.”