Boris Johnson backed the Prime Minister on the Leveson report but suggested that police briefings to the press would continue.
The Mayor, speaking to reporters in India where he is on a trade mission, said: “I think the tenor of what the Prime Minister has had to say this afternoon is absolutely right.
“He puts his finger on the real difficulty of framing any kind of legislation to underpin the independent commission that wouldn’t end up fettering the freedom of the press.
“That for me is the key difficulty and I think David Cameron has got it right.”
He applauded the proposal for an independent commission that would not have any current newspaper editors sitting on it.
“Having some of the present lot actually running the PCC is like having the Boston strangler in charge of regulating door to door salesmanship,” he said.
“What is being proposed is a much greater degree of independence and I think that’s the right way to go. I think the public need greater reassurance and greater protection from the excesses and bad behaviour of the media.”
However, Mr Johnson, who is responsible for the Met, said he thought off-the-record briefings from the police would continue.
“Clearly briefings are going to remain an important part of public life. Officials one way or the other are going to have to have trust in the media,” he said.
“On the whole when it comes to the Metropolitan Police Service, it is clear that where there have been problems, Lord Justice Leveson says those problems have now been very substantially dealt with”.
The Mayor denied he was worried about an overly cosy relationship between the media and politicians.
“The relationship between journalists and politicians is like that between a dog and a lamppost and that’s how it should be. There should be a healthy friction,” he said.
And he played down concerns that the Prime Minister would struggle to build bridges with deputy Prime Minister Nick Clegg over press regulation.
“I’m sure that if they can create a coalition they can get agreement on this,” he said.