Iraqi cleric Sheikh Abdul Mahdi Karbalai warns of 'threat to peace'

A representative of the highest Shia authority in Iraq, Grand Ayatollah Ali Sistani, has called for a national stance against the militant group ISIS.

His representative, Sheikh Abdul Mahdi Karbalai, spoke exclusively to the BBC's John Simpson.

''This danger could spread - it will threaten peace in the entire region,'' he said.