After about 20 seconds, the swimmer will start to sink and will hold his breath underwater for anywhere from 30 to 90 seconds.

CNN: Water safety expert: 'Drowning doesn't just happen'

He may well be right about the scepticism amongst voters "out there", but he had better not hold his breath waiting for the attorney general's advice to be published.

BBC: Prime Ministers Questions

But Mr Staley should not hold his breath.

ECONOMIST: American bank bosses

Each song lasts as long as the lead singer can hold his or her breath.

UNESCO: CULTURE