The sharks were well-fed

A spokeswoman for the aquarium said Mr Prescott had made the visit on Saturday morning.

He was told about the diving facilities at the Fife aquarium by Chancellor Gordon Brown, whose Dunfermline East constituency is nearby.

Mr Prescott made the visit while in Scotland to speak at a Labour Party dinner in Fife, along with Mr Brown, on Friday evening.

He described the experience as "exhilarating".

He said it was a far cry from his previous diving experiences.

John Prescott: Keen diver

"I have never seen such big animals so close before," he said.

Mr Prescott added: "I have a lifetime of enthusiasm for the sustainability of our seas.

"To swim not only with sharks but also with 3,000 different varieties of fish was most impressive."

The aquarium spokeswoman said Mr Prescott had been "brave and fearless", since many people had second thoughts before entering the shark-infested tank.

She added: "His dive was in the morning. It's a particularly good time to swim with the sharks as they tend to be quite well-fed at that time."