Key Points:

John Key would "turn gay" for Brad Pitt, he told the gay magazine Express.

The joke question "Who would you turn gay for?" has been immortalised by the Australian television chat show host Rove McManus.

Politicians often avoid answering it, as Australian Prime Minister Kevin Rudd has done twice on McManus's show.

But Mr Key, aged 47, had no such qualms.

"Who would I go gay for? ... Brad Pitt," he told Express. "Now he's a bit older, he's a bit of a looker. I was going to say Tom Cruise, but someone of his age shouldn't look that young."

Cruise is 46 and Pitt 44.

Asked about gay marriage, Mr Key said he felt there was no need to go beyond the existing civil unions law. But he did not oppose gay couples adopting children.