Bats are ruining churches because of barn conversions, the Bishop of Norwich has said.

Speaking in the house of Lords, the Rt Revd Graham James said that bats had moved into churches in his diocese because old barns were being made into homes.

"All over Norfolk there are barns once used by bats which have been turned into beautiful homes for human beings. And their new owners do not want to share their property with them. And so the bats have moved to medieval churches," he said.

Speaking in support of a bat conservation bill sponsored by Conservative peer Lord Cormack, he said that worshippers in some areas had "come to the end of their tether" because their "glorious building" had become "increasingly unusable for worship or any other community purpose".

"I think we tolerate this because we think houses of God are not inhabited. But they are, and not only by God - they are inhabited by people," he said.

Bat droppings can cause damage to church fittings such as fonts and pews, and require intensive cleaning by volunteers if the church is to be used for services.

Around 60 per cent of pre-16th century churches are estimated to contain bat roosts.