Anti game-hunting campaigners say they have photographic evidence of two illegal hunters in the Greater Blue Mountains World Heritage Area in New South Wales.

A group of bushwalkers claim they came across a pair of hunters with rifles strapped to their backs near Tigersnake Canyon last Saturday.

The National Parks and Wildlife Service says the incident was reported to them, but authorities were unable to locate the men.

Plans to introduce recreational hunting in national parks are on hold, pending the outcome of a report into the Game Council.

The program would allow amateur hunters to eradicate pests in some NSW national parks.

But the National Parks Association's Justin McKee says that plan is dangerous.

"An incident like this in a high tourism area demonstrated the potential for conflict between the public and armed hunters," he said.

"Hunting in national parks is bad policy, its bad for tourism, public safety and the environment.

"It ruins the international reputation of our national parks brand that has taken 50 years to build up."