Clad in nothing more than white underwear and covered with streaks of body paint, animal activist Ashley Fruno stood outside the Anson Road office of Air France on Thursday afternoon.

Splashing white, blue and red paint on her body to symbolise a "bloodied Air France logo", she also clutched a sign that read: "Air France: Stop Monkey Cruelty".

It was a silent protest. The lone activist from the Asia office of international animal rights advocacy group People for the Ethical Treatment of Animals (Peta) spoke only when onlookers spoke to her. They also snapped pictures and posed with Ms Fruno.

"Air France is the only major airline in the world still transporting monkeys destined for experimentation," Peta Asia said in a statement.

Other airlines such as China Southern, Air China, China Eastern, Vietnam Airlines, Philippine Airlines, United Airlines, and Cathay Pacific have already banned shipments of primates to laboratories, it added.

"(Laboratories are) where they are caged, cut into, poisoned and killed," Peta Asia said. Animals including monkeys, rats, rabbits and dogs are often used as test subjects in the pharmaceutical and cosmetic industries, where they are injected with drugs and their reactions monitored.

But animal rights groups, including local wildlife rescue group Animal Concerns Research and Education Society (Acres), have long slammed this practice.

Instead, they point to alternatives such as in-vitro testing. This is where human cells are grown in a system to copy the structure and function of human organs and organ systems, avoiding the need to test on animals.

Aside from the end faced by monkeys used in such tests, the process of transporting them is also inhumane, Peta Asia said. "They are crammed into tiny wooden crates before being loaded into cargo holds," they said.

Ms Fruno added: "Air France is out of step with the rest of the airline industry."