US pop star Katy Perry gave Tony Abbott a lecture on gay marriage the last time she was in Australia, but this time around she had trouble remembering the prime minister’s name.

The singer, in Sydney to promote her coming world tour, was quizzed about her knowledge of Australia on Wednesday.

Asked by Seven Sunrise host Samantha Armytage if she knew the name of Australia’s prime minister, she replied: “This guy I was on the phone with that I don’t agree with, but I like him a lot … Tony?”

She didn’t do much better on Australian fauna, saying she thought wombats were fictional.

Before the live interview, hundreds of screaming fans lined up to see the 29-year-old outside the network’s studios in Martin Place.

Perry took selfies and signed autographs on the red carpet, greeting fans ranging from preschoolers to grandmothers.

“Where’s my coffee?” the pop star joked as she sat down for her interview.

She was soon back on her feet when her hosts surprised her with an Australian petting zoo featuring a baby saltwater crocodile, a koala, a wombat and a diamond python.

“I never thought I’d see a wombat in person because I thought it was a fictional animal,” she said.

“But Australia has all kinds of animals. Do you have a pegasus?”

Perry last week announced her Prismatic World Tour is coming to Australia in November, but has not confirmed who will be touring with her.

Preparations for her arena shows were already under way, she said.

“I’m really focused right now,” Perry said. “I’ve cut out all alcohol.

“I’m almost 30, guys. My body doesn’t snap back any more. I can’t just go around eating McDonald’s like I used to.”