Former culture secretary Lord Smith has admitted he should have “pushed further” on press regulation after the death of Princess Diana.

Smith, secretary of state from 1997 to 2001 under Tony Blair, said changes made to the Press Complaints Commission resulted in a “palpable change of behaviour” from the press but standards had slipped "egregiously".

He said: “I have to hold my hands up and say the changes which we were able to secure in 1997 and which lasted for a two or three year period in terms of their impact and effect, I regret that I didn’t see properly at the time that this wasn’t enough and we should have pushed further.”

Smith said he received 1,200 letters from members of the public criticising reporters and the paparazzi following Diana’s death.

He added: “There are moments when the balance changes in the government’s favour [as opposed to the press] and the death of Diana was one such moment, where there was a clear public demand for change.”

Smith said Lord Wakeham, PCC chairman at the time, was the “nearest we have come” to an individual capable of commanding the respect of the entire press, calling the role of PCC chair “both a regulator and a champion”. He told Lord Justice Leveson the key to independence of a new press regulator was having an "unimpeachably independent" chairman.

He went on to call the PCC “a champion of the free press” but admitted the role of the body had never been properly outlined.

Lord Justice Leveson said he would consider it “a real failure” if after two years the press reverted to unethical behaviour and said it may be difficult to find an individual who can demand the respect of the press with the confidence of politicians and the public.