The area, in Mondulkiri and Rattanakiri provinces, is home to several indigenous hill-tribes whose first main contact with the outside world was during the Vietnam War when their territory was crossed by the myriad paths of the Ho Chi Minh trail.

Dany Chheang, deputy director of the Agriculture Ministry's Wildlife Protection Office, said allowing foreigners to pay to shoot game was far better for conservation than having poachers take it illegally.

"Illegal hunters are burning dollars every day," he told Reuters. "We have not explored all the potential of our natural resources. Now is the time to do so."

"The money we net will be invested in preserving the animals and forest. It is better for sustainable development than letting local hunters deal with cheap black markets."

He did not say what the 30 approved species were. The forest area is thought to be one of southeast Asia's last wildernesses and is home to wild elephants and tigers.

Environvmental group WWF, which has been promoting wildlife conservation in war-scarred Cambodia since 1998, said it was concerned about the plan, which has been in the pipeline for two years but which has remained shrouded in secrecy.

WWF's Cambodia programme manager, Bas van Helvoort, said little was known about animal population numbers in the two provinces, and so allowing them to be hunted could be disastrous.

"Putting species up to be hunted is not going to contribute to making them safe," van Helvoort said. "This has been done in Africa but it is very carefully selected and very controlled."

So far, Phnom Penh -- which is routinely accused of allowing rampant illegal logging -- appears oblivious to the concerns.

"These are our natural resources. We do not need permission from wildlife conservation experts to run our business," Dany Chheang said.

The Finance Ministry was still working with agriculture officials on the finer points of the plan, such as trophies and fees, he added.