Australia is using cute and cuddly koalas as a secret public relations weapon to win over world leaders during the G20 in Brisbane next week.

Staff at a Brisbane zoo are training koalas so they are ready to cuddle the world's most powerful people during the G20 leader's summit.

The Lone Pine Koala Sanctuary is famous for its koala cuddling sessions, and management expects VIPs such as Russian president Vladimir Putin and his US counterpart Barack Obama to have photo- ops with the animals during the two-day summit.

But the koalas are fussy creatures sleeping for up to 20 hours a day, so handlers at the sanctuary are training the animals to become extra familiar with humans ahead of the G20 visit.

"As young trainees, koala cuddles are limited to just 10 minutes a day, graduating to no more than half an hour a day as adults. Even then, after three days of cuddles, it's time out for the koalas and a cuddle-free day before returning to work," Karen Nilsson, head koala-keeper at the Lone Pine Koala Sanctuary, told RT news.

"Koalas spend a lot of their time resting and sleeping, so by limiting it to half an hour, maximum, we are not interrupting their usual routine."

Previous VIP koala cuddlers at the sanctuary have included Pope John Paul II, Soviet leader Mikhail Gorbachev and American pop star Taylor Swift.

Staff advised potential koala huggers to keep calm and act " like a tree".

"The number one tip is to pretend you're a tree, that's what koalas are used to. When you hold a koala stay nice and still, give them good support on their bottom so they know they are not going to fall," Nilsson said.