He criticised the scenes he watched on TV, but said it was possible to have confidence and be “unhappy” about how the vigil was policed.
He added: “I think it’s possible to have confidence in the Commissioner but be unhappy about how the vigil was policed.
“I think the Commissioner – and the police in the modern era in the last few years in particular – is under more scrutiny than any commissioner in history.
“The Commissioner regularly appears before select committees in the Commons, regularly appears before committees in the [London] Assembly, regularly explains what the police are doing to myself or the Home Secretary and through the media to ordinary Londoners.
“It’s a tough tough job and she has my confidence and my support. But that doesn’t mean it’s always going to be 100 per cent.
“I said on Saturday I was unhappy with the policing. One of the things about having mutual trust and respect for each other is its possible to have confidence in that person’s ability to do the job but be unhappy about a particular event.”