Keir Starmer faces investigation for 'misleading' Parliament as suspended Labour MP turns on PM

"There are evident inconsistencies between statements made at Prime Minister's Questions and the evidence given by Sir Olly Robbins to the Foreign Affairs Select Committee," Mr Turner wrote.

He argued that "these discrepancies raise important questions that go to the heart of transparency and accountability in Parliament."

The former Labour MP insisted that a Privileges Committee referral "would allow for a thorough and independent inquiry, ensuring that the House and the public can have full confidence in the accuracy of statements made to Parliament."

Mr Turner secured his Kingston upon Hull East seat as a Labour candidate during the 2024 general election but subsequently lost the party whip after conducting an interview with Jody McIntyre, a campaigner who had previously contested against Jess Phillips for George Galloway's Workers Party.

GB News Political Editor Christopher Hope characterised the development as "dangerous ground for the Prime Minister."

Conservative leader Kemi Badenoch is understood to be pursuing a similar course, seeking Sir Keir's referral to the same parliamentary body that ultimately ended Boris Johnson's career after determining he had misled the Commons over Partygate.

Cross-party pressure is mounting, with Liberal Democrat Business spokeswoman Sarah Olney declaring to GB News: "We very much want to see the Prime Minister referred to the Privileges Committee."

Prior to his Privileges Committee demand, Mr Turner had already confronted the Prime Minister in the Commons about eroding public confidence as local elections approach.

He told Sir Keir: "The trouble that we all face is that trust in the Prime Minister, and in politics, is diminishing as this sorry saga continues."

With just over a fortnight until voters head to the polls, Mr Turner pressed the Prime Minister on what steps he would take to restore faith in himself and the Labour Party.

Former shadow chancellor John McDonnell launched a pointed attack on Morgan McSweeney, Sir Keir's former official who maintained close ties with Lord Mandelson.

"What Mandelson wants, Mandelson gets," Mr McDonnell said, drawing heckles from Cabinet members.

He suggested the Prime Minister had become reliant on McSweeney and Mandelson to organise and fund his leadership campaign, with the Washington ambassadorship serving as Lord Mandelson's reward.

Diane Abbott, the Mother of the House and Independent MP for Hackney North and Stoke Newington, reminded colleagues of Lord Mandelson's two resignations from Tony Blair's cabinet during the 1990s and early 2000s.

The former Shadow Home Secretary said: "Peter Mandelson has a history...The question is, why didn't the Prime Minister ask?"

Sir Keir acknowledged his error directly: "I should not have appointed Peter Mandelson."

He explained that upon learning of further revelations, he requested the Cabinet Secretary examine the process to provide assurance about procedures.

The Prime Minister expressed astonishment that Foreign Office senior officials failed to alert him to relevant concerns even when he ordered a review of the UK Security Vetting service.

Labour backbencher Neil Duncan-Jordan questioned why Lord Mandelson was ever considered for such a significant role, prompting Sir Keir to respond: "I've accepted that that was my decision and I've apologised for it."