Michael Grade, chairman of the BBC, has admitted that the corporation has "unwittingly contributed" to the decline in serious news values because of its preoccupation with audience accessibility.

Delivering a lecture in honour of Hugh Cudlipp, the former editor of the Daily Mirror, Grade said that the rise of rival news networks had increased competition for audiences and put "serious news values... under increasing strain''.

He also said the school of "why is this lying bastard lying to me?" school of journalism practised by Jeremy Paxman had "outlived its usefulness".