'Plebgate': Mitchell 'lacks confidence' in Met chief
Tory MP Andrew Mitchell no longer has "confidence" in Metropolitan Police Commissioner Bernard Hogan-Howe, the BBC understands.
Sources close to Mr Mitchell said he had found an exchange of letters between the two "unsatisfactory".
The Met is currently investigating events surrounding a row with police in Downing Street which saw Mr Mitchell resign as chief whip after he was accused of calling officers "plebs".
The MP met David Cameron on Monday.
Mr Mitchell has admitted swearing at officers during the incident in September, but denies using the word "plebs" during angry exchanges at the gates to Downing Street.
He resigned from the government in October, following several weeks of criticism in the media, with the affair being nicknamed "plebgate".
But CCTV footage has cast doubt on the original police accounts of the row and the Met has launched an investigation - Operation Alice - to look at events.
Friends of Mr Mitchell, MP for Sutton Coldfield, have suggested he should return to government.
Mr Cameron, speaking on a trip to Afghanistan, praised the former chief whip's "calm and rational" response to the affair, adding that he had "a lot of sympathy" for his predicament.
Two people have been arrested during Operation Alice - a policeman and a 23-year-old man not employed by the police.
The BBC understands that Mr Mitchell has met Pat Gallan, a deputy assistant commissioner, who is in charge of the Metropolitan Police's Directorate of Professional Standards and is overseeing the investigation.
Political correspondent Gary O'Donoghue said he had been told Mr Mitchell regarded Ms Gallan as "extremely good" though he no longer had "confidence" in the Met commissioner himself.
Earlier this week, Mr Hogan-Howe publicly backed the two original officers who were present during the altercation in Downing Street.
There has also been what is described as an "unsatisfactory" exchange of letters between Mr Mitchell and the commissioner, which has reportedly further eroded his confidence.
The Met said they had no comment to make at this stage.