Dressed in a schoolboy's uniform, Bruno told assembled media that he had spent the night with Rudd after they both appeared on the same live TV chat show Sunday, adding: "Nothing happened. We just stayed up all night talking.
"The reason I'm late is I just had breakfast in bed with Kevin Rudd. That guy is like, uber-cute," he said.
"I thought Obama was like the hottest guy in the world until I met Kevin."
Speaking in Sydney, known for its annual Mardi Gras gay parade, Bruno said he was surprised at the locals' lack of fashion sense.
"To be honest I'm a little bit disappointed because I know 150 years ago Britain sent all their gay guys over here, so ich expected a little bit more flair," he said.
Bruno's glowing assessment of Rudd contrasted sharply with his comments about British Prime Minister Gordon Brown at the movie's British premiere this month.
"The guy needs a total makeover. He needs a fake tan, he needs to wear some tight slacks... Gordon, click those heels and say hello," he said.
Rudd revealed Monday that he was nervous about appearing with Baron Cohen -- perhaps fearing a stunt similar to the MTV Awards, when Bruno's bare buttocks were lowered on to rapper Eminem's face.
However, Rudd and Bruno were never on screen together during the show, meaning the prime minister escaped any embarrassing moments.
"It takes courage or foolhardiness to appear on any television show with that guy... I'm just happy to have survived," Rudd told reporters.
"Bruno" premieres in Sydney later on Monday.
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