BORIS Johnson has “impugned the integrity” of the House of Commons with his bombshell resignation speech, a senior MP has claimed.

The former Prime Minister has been under investigation about whether he knowingly misled the Commons over Partygate.

Mr Johnson announced his resignation from his constituency of Uxbridge and South Ruislip, in west London, on Friday night.

He accused the privileges committee which has been probing him of “egregious bias”, adding that he is “bewildered and appalled”.

Gazette: Critical - Harwich and North Essex MP Sir Bernard JenkinCritical - Harwich and North Essex MP Sir Bernard Jenkin (Image: Chris McAndrew/UK Parliament)

He said: “Their purpose from the beginning has been to find me guilty, regardless of facts. This is the very definition of a kangaroo court.”

Mr Johnson’s statement has been condemned by Harwich and North Essex MP Sir Bernard Jenkin, who sits on the committee.

Sir Bernard said: “No member of the privileges committee will comment on the report which we have yet to publish.

“As a committee spokesman has made clear, the committee has followed the procedures and the mandate of the house at all times and will continue to do so.

“Mr Johnson has departed from the processes of the house and has impugned the integrity of the house by his statement.

“The committee will meet on Monday to conclude the inquiry and to publish its report promptly.”