Hytner alleges that many of London's critics are biased when it comes to shows directed by women. The comments come in the wake of bad reviews for the National's adaptation of the Powell/Pressburger classic movie, "A Matter of Life and Death," directed by Emma Rice.

Speaking to The Times, Hytner said, "They would be horrified by the accusation, but I'm afraid I'm making it. I think it's fair enough to say that too many of the theatre critics are dead white men. They don't know it's happened to them, but it has."

Hytner pointed out that that some of London's critics were in their jobs when he was still at university and that many reviews by male critics are "misogynistic," especially for shows directed by gay women.

The artistic director, whose regime has seen an increase in women directors at the National since he was appointed in 2003, said that the reviews by female critics of Rice's production were predictably more favorable.

Hytner went on to say, "In private the female critics are voluble about this. I know that (National director) Katie Mitchell gets misogynistic reviews, where everything they say is predicated on her sex. Gay males have never had a problem in the theatre... The ones who have it worst are the gay women. They really get it in the neck and there's a lot of sniggering."

Michael Billington, who has been The Guardian's critic since 1971, hit back at Hytner's comments, calling them "ballderdash and piffle."

"It seems to me to be ageism. We are not dead, whatever else we are," said Billington. "And the idea that critics review productions on the basis of gender and sexual orientation is absolute nonsense."