Novelist Ian McEwan has criticised the views of church leaders who have challenged assisted dying.

The Atonement author made the comments at the Charleston Festival in East Sussex over the weekend around the publication of his next novel, The Children Act.

The novel explores the issue through the eyes of a high court judge presiding over the case of parents who refuse treatment for their sick child because of their religious beliefs.

"What is ridiculous is the law allows people to starve to death, but when somebody is suffering extreme pain they cannot get the nurse to help them die," McEwan said.

"People who want to die should be allowed to die. The good thing is that in common law it is now moving."

He continued: "The issue has been confused by churchmen who sit in the House of Lords. What they have said is insane – medieval."

McEwan made similar comments at the Oxford Literary Festival in March when he said denying medical help on religious grounds was "utterly perverse and inhumane", and "the secular mind seems far superior in making reasonable judgements".

Lord Falconer's Assisted Dying Bill would make it legal for doctors to prescribe terminally ill patients with lethal doses of drugs where they have requested them. Peers are due to vote on the legislation in the summer.

Back in 2005, McEwan expressed his scepticism towards religion in general.

"I'm not against religion in the sense that I feel I can't tolerate it but I think written into the rubric of religion is the certainty of its own truth. And since there are 6,000 religions currently on the face of the Earth, they can't all be right.

"And only the secular spirit can guarantee those freedoms, and it's the secular spirit that they contest."

The Children Act is out on 4 September from Jonathan Cape.