The as-yet-unnamed scent (Eau de Fur? Koala No. 5?) was revealed in an interview with Women's Wear Daily.

Pernet was in London this week for the city's Fashion Week.

She told WWD that "fashion, film and fragrance are the loves of my life".

But she has one other love - koalas.

"I am so in love with koalas! I've always had a thing for them," she said. "Growing up, I had a friend from Sydney, and we would all have toy koalas on the end of our pencils. Then, the last time I was in Perth, Australia, I said I'd only go if I could hold a koala because it's been a dream since childhood. So I got to hold one called Sunshine, and I was so surprised by how heavy she was."

Her love of the tree-hugging marsupial had also led her to find out about the problems they face: chlamydia, bushfires and urban development.

So she talked to Celso Fadelli, head of the Intertrade Group – who she is working with on a line of fragrances – that she wanted to do something to raise money for Save The Koala.

She planned to use eucalyptus as a part of the fragrance.

But so far it's proven difficult.

"It's far too strong, and it smells kind of like medication," Pernet admitted to WWD. "It's a difficult material to work with, but I'm sure we'll arrive at something good."

According to the Australian Koala Foundation, koalas generally "smell like cough drops or a pleasant eucalyptus smell", though mature males tend to be a bit more musky.

Sunshine the koala is a familiar furry face on the celebrity circuit.

In January the marsupial received a kiss from Serena Williams ahead of the Hopman Cup circuit.

The tennis player pronounced Sunshine "really cute" but, despite putting her name to several fashion lines, has yet to announce a koala-inspired collection.