UNITED NATIONS - Native Americans want U.S. authorities to cancel plans to detonate 700 tons of explosives on what they say is tribal land in Nevada.

The planned explosion, scheduled for June 2 some 90 miles from Las Vegas, is aimed at aiding U.S. efforts to develop ""bunker buster"" weapons capable of penetrating solid rock. Officials have suggested the test would constitute the largest non-nuclear, open-air blast in the test site"s history.

Federal officials have described such efforts as essential to the administration of President George W. Bush"s self-styled ""war on terror"" but to leaders of the Shoshone, also known as the Newe people, the planned detonation is just the latest in a decades-long history of experiments at the Nevada Test Site to shake the earth and raise a dust cloud.

""We are opposed to any further military testing on our lands,"" said Raymond Yowell, chief of the Western Shoshone National Council.

The site of the latest proposed test sits on the land recognized under the 1863 Treaty of Ruby Valley as part of the tribe"s national territory, Shoshone leaders said, and the U.S. military therefore has no right to use it.

The U.S. government disagreed and has asserted its ownership of the land.

""Without going through a lot of detail, the issue of ownership of the land area occupied by the Nevada Test Site, and for that matter very large sections of Nevada and Utah, is very complex (going back to the Ruby Valley Treaty) and in our eyes has been resolved,"" said Kevin Rohrer, a spokesman for the National Nuclear Security Administration, which operates the test site.

The U.S. Supreme Court had ruled in 1985 that the Shoshone had been paid in full for the land under the Indian Claims Commission Act of 1946 ""and thus the land is property of the United States Government,"" Rohrer said in an email.

""My understanding is that funding has been set aside in a trust account for compensation but there is disagreement among Western Shoshone on whether they should accept the funding,"" he added.

Shoshone elders rejected the government"s position and last month won a victory in their fight to reclaim territory when the Geneva-based UN Committee on the Elimination of Racial Discrimination (CERD) said in a report that Washington"s claim to the Western Shoshone land ""did not comply with contemporary human rights norms, principles and standards that govern determination of indigenous property rights.""

Among other things, the panel cited special concern over the existence of nuclear waste dumped on tribal territory without consulting and over the objections of the Western Shoshone people. The 18-member panel also asked Washington to ""freeze, desist and stop"" actions being taken against the Western Shoshone Nation.

In the ruling, CERD also cited concern over weapons testing at the Nevada Test Site as well as efforts to build a high-level nuclear waste depository at Yucca Mountain.

Tribal elders said Washington"s plans to proceed with the June test in the face of the UN panel"s findings was a slap in the face of the international and Native American communities.

""This is a direct violation of the CERD"s finding and an affront to our religious belief,"" Yowell said. ""Mother Earth is sacred and should not be harmed.""

The U.S. military tested nuclear weapons at the Nevada site from 1951 until 1959. Some analysts have said they believe that even after signing the Limited Test Ban Treaty with the Soviet Union in 1963, the U.S. continued to conduct underground tests in the area for several years.

Scientists have said that exposure to radiation from nuclear testing caused an increased incidence of leukemia and cancer in areas adjacent to the Nevada Test Site.

All necessary permits to conduct the test have been obtained from Nevada state agencies, test authorities have said, but there has been no indication that they sought Shoshone approval.

The test has been named ""Divine Strake,"" adding to the outrage felt by many Native Americans, who say the test site sits on sacred land.

""It"s a mystery why they call it "divine","" said Carrie Dann, a grandmother and executive director of the Western Shoshone Defense Project. ""Isn"t "divine" used for your deity, God, your sacredness? Why don"t they call it "Hell Strake?"""

""When you are working testing weaponry of destruction of life, you should not associate it with "divine","" Dann added. ""We want this insanity to stop. No more bombs and no more testing.""