Newsnight presenter Jeremy Paxman went too far when he talked about religious hogwash and stupid people who believe in the Old Testament, the BBC Trust has ruled.

Paxman made the comments in an interview with Professor Richard Dawkins, the outspoken author of The God Delusion, prompting one viewer to complain that the presenter of BBC2's Newsnight was biased and offensive.

The trust's editorial standards committee rejected the accusation of bias, but said Paxman might have unintentionally caused offence with the comments which had no clear editorial purpose.

Originally, BBC management rejected the complaint in its entirity, denying that Paxman had shown any anti-Christian bias and saying the presenter had played devil's advocate to Dawkins, who was on the programme to talk about his new book, The Magic of Reality: How We Know What's Really True, on 13 September 2011.

However, the complaint then went to the BBC Trust editorial standards committee, which ruled that Paxman had a well-known interviewing style and viewers would have expected a lively discussion between the pair on the programme.