SYDNEY: Australian Prime Minister Kevin Rudd Thursday gave new opposition leader Tony Abbott's tight-fitting swimming briefs the big thumbs-down, declaring he would vote against them in a referendum.

Rudd urged Abbott, who was pictured posing in his "budgie-smuggler"Speedos and lifesaver's cap on a Sydney beach this week, to opt for the less revealing "boardies" or board shorts.

"If there was a referendum tomorrow between budgie-smugglers and boardies, I think I would be voting for boardies," Rudd smiled.

"There should be certain things the Australian people are protected from, and that's national political leaders so attired."

Abbott, a fitness fanatic and ex-boxer, defended his choice of swimwear, saying they were "compulsory" at Queenscliff Surf Life Saving Club in Sydney's north.

The incident evoked memories of Peter Debnam, a politician from Abbott's Liberal party whose failure in 2007 to win the leadership of New South Wales state was linked to his penchant for Speedos.

"Oh God, not again. One day scientists will discover why Liberal leaders are genetically programmed to be photographed in Speedos," wrote Daily Telegraph columnist Joe Hildebrand.