A saltwater crocodile lies on the banks of the Adelaide river near Darwin in Australia's Northern Territory

Australia on Thursday rejected a plan to let big-game hunters shoot crocodiles in the country's tropical north, saying the scheme risked encouraging "cruel and inhumane" behaviour.

Under the proposal about 50 crocodile safaris a year were to be allowed in the Northern Territory, where the giant reptiles have become increasingly common since they were declared a protected species in 1971.

Australian Environment Minister Greg Hunt said the federal government had considered allowing "trophy hunts" but did not believe they were appropriate.

"My view is that there was a risk of cruel and inhumane treatment," he told reporters. "That was, in my view, inappropriate."

Backers of the plan, including the Northern Territory government, argued that around 500 saltwater a year are culled in the area anyway, so safaris would be just another way of killing them.

They also said that hosting big-spending trophy hunters would provide a valuable source of income for the impoverished Aboriginal communities who live in the regions where most crocodiles are found.

The Northern Territory government said the "short sighted and ill-informed decision" to reject the plan squandered a chance to reduce welfare dependency in indigenous communities.

A saltwater crocodile being enticed with meat out of the Adelaide river near Darwin in Australia's Northern Territory

"Crocodile safari hunting is a real opportunity for economic development and it would create wider tourism opportunities," NT Parks and Wildlife Minister Bess Price said.

"Greg Hunt is listening to the wrong people. He needs to listen to the people on the ground in the bush. He has made the wrong decision."

Conservation groups had opposed the plan, saying allowing hunters to blast away at native wildlife would send the wrong message in an area heavily reliant on eco-tourism.

Humane Society International said the Northern Territory government had been unsuccessfully pushing to allow crocodile hunts for 20 years.

"It is time that the Northern Territory stopped taking its proposals from past centuries and instead considers how native animals like can provide benefits such as eco-tourism or other ventures," the campaign group said.

Saltwater crocodiles, which can grow up to seven metres (23 feet) long and weigh more than a tonne, are a common feature of Australia's tropical north, with their population estimated at over 150,000.

They kill an average of two people a year. In the latest attack in January a 12-year-old boy was snatched while swimming in a waterhole at the Kakadu National Park east of Darwin.