"If they could kill me to save those 500 kangaroos, I'd do it," Tent Embassy member Robert Cragie said. "They're innocent, they don't know what's going on. I do, so come on, jab me with a needle, kill me instead."

Four hundred eastern grey kangaroos will be killed with a lethal injection on the old naval site in Belconnen after the ACT Government cancelled the Department of Defence's original plan to move them. An expert panel headed by ACT Commissioner for the Environment Dr Maxine Cooper found relocation would be inhumane. The RSPCA, which will witness the cull, does not support moving the kangaroos.

The decision to cull has drawn national and international attention, with some Japanese media contrasting it to Australia's criticism of Japanese whaling.

Sir Paul McCartney last week endorsed an international website condemning the move.

Mr Cragie said the kangaroo cull was particularly disturbing to indigenous people.

"If you could see the kangaroos through our eyes, you would see how important this is to me," he said. "This cull is genocide, because these kangaroos are my brothers, they're my sisters, they're my aunties, my uncles and my babies."

Animal Liberation ACT organised the protest to try to reverse the ACT Government's decision to cull kangaroos. Members of Animal Liberation ACT and the indigenous community refuse to leave the site until the cull is cancelled.

"It only took four people to start the Tent Embassy, and all of us here, that's all it takes to stop this senseless killing. If there were 10,000 people here by Wednesday, they wouldn't do it," Mr Cragie said.

Crowd members travelled from Sydney, Victoria and regional areas to be present at the protest.

Australian actress and Rights for Roos spokeswoman Fiona Corke travelled from Victoria.

"Kangaroos are protected, it's ridiculous. I'd hate to imagine what would happen to them if they weren't protected," she said.

"I've heard the Government saying the cull is for conservation, but it's not, it's about development."