ABORIGINAL traditional owners have declared they want the multibillion-dollar Jabiluka uranium deposit to remain undeveloped and be incorporated into Kakadu National Park.

A senior traditional owner, Yvonne Margarula, says her Mirarr people are "deeply saddened" that for more than 30 years uranium that should never have been disturbed on their land at the Ranger mine in the Northern Territory has been exported to Japan to be used by nuclear power companies, including at the stricken Fukushima plant, which was heavily damaged by the tsunami last month and has been leaking radiation.

Ms Margarula told the Herald that in the Mirarr people's Dreaming a sacred dangerous power called Djang was unleashed when it was disturbed on their land.

She said her late father, Toby Gangale, warned the Australian government in the late 1970s that Djang "might kill all over the world" if disturbed at Ranger, which was built despite opposition from traditional owners.

"No one listened to him," she said.

Ms Margarula and 70 others in her clan could be among Australia's richest people if they allowed Energy Resources of Australia to develop Jabiluka, which was halted in 1998 after an eight-month blockade by 5000 protesters.

The 72 square kilometre mineral lease containing 141,640 tonnes of uranium is one of the world's largest undeveloped uranium deposits. ERA, 68 per cent owned by Rio Tinto, is eager to mine the high grade deposit worth $18.5 billion.

Speaking in Jabiru, a town near the Ranger mine and Jabiluka deposit, both on land owned by the Mirarr people, Ms Margarula said Jabiluka is a sacred place and she never wanted to see it disturbed.

In a letter to the United Nations Secretary-General, Ban Ki-moon, this week, Ms Margarula said it was "with great sadness" the Mirarr people learnt of the suffering of the Japanese people following the earthquake and tsunami.

Ms Margarula told Mr Ban her people had been blocked from opposing the export of uranium from their land to Japan.

"Given the long history between Japanese nuclear companies and Australian uranium mines, it is likely that the radiation problems at Fukushima are, in part at least, fuelled by uranium derived from our traditional lands," she wrote.

Ms Margarula, a shy, softly spoken elder, said her people had decided they wanted the federal government to support the incorporation of the Jabiluka site into the Kakadu park, as it had for another uranium mining area at Koongarra, near the renowned Nourlangie Rock.

That decision angered the French energy group Areva, which holds the mineral lease over the 12 square kilometre site that contains 14,000 tonnes of uranium worth billions of dollars.

Jeffery Lee, the sole member of the Djok clan, offered Koongarra to the government, shunning the chance to become a billionaire, saying he is happy to work as a ranger protecting the land.