WASHINGTON – Conservative activists are pressing the Bush administration and Republican lawmakers to reverse their support for an international oceans treaty they claim will limit American sovereignty and empower an international body akin to the United Nations.

They want President Bush to repudiate a treaty called the U.N. Convention on the Law of the Sea, just as he pulled America out of an agreement creating the International Criminal Court and has refused to sign the Kyoto treaty on greenhouse gas emissions. The White House says it wants to see the treaty ratified soon.

Although the oceans treaty may be obscure, it is stirring intense passions among conservatives who see it as internationalism’s latest encroachment on American sovereignty.

The treaty has created “another unaccountable, politicized multilateral tribunal,” said the president of the Center for Security Policy, Frank Gaffney. The treaty, which came into force in 1994 and has been signed by 148 countries, created an International Seabed Authority to oversee extraction of resources from the seabed. The authority has an assembly, a council, and a secretariat; an International Tribunal for the Law of the Sea was also created to resolve disputes.

More than a dozen groups that helped elect the Republican majority in Congress plan to flex their political muscle during a press conference Friday and denounce the treaty during the three-day Conservative Political Action Conference, which bills itself as the largest annual gathering of conservative grassroots activists from around the country.

Vice President Cheney, White House political adviser Karl Rove, and several senators eyeing presidential bids in 2008 will speak at the gathering.

Groups that plan to protest the treaty include the American Conservative Union, the Competitive Enterprise Institute, the Family Research Council, and the Eagle Forum. A former presidential contender, Patrick Buchanan, will also lodge his objections.

The groups are targeting the treaty not only to protest specific provisions they say will hamper the development of undersea mining, but its “collectivist” vision that the seabed is the “common heritage” of all nations, regardless of whether they possess a coastline.

“It creates what looks like a second U.N. at a time when the first U.N. is not running very well,” said a former Reagan administration official who was involved in American attempts to renegotiate the treaty, Doug Bandow.

The treaty was championed by the chairman of the Senate Foreign Relations Committee, Senator Lugar, a Republican of Indiana, and unanimously endorsed by the committee a year ago. However, it did not reach a floor vote. To become law, the treaty must be ratified by two-thirds of the Senate.

The Bush administration says the treaty would give America stronger legal protections for marine exploration and military and commercial navigation.

“As a matter of national security, economic self-interest, and international leadership, the administration is strongly committed to U.S. accession to the U.N. Convention on the Law of the Sea, and we urge Congress to provide advice and consent to the treaty as early as possible in this Congress,” said a spokesman for the White House Council on Environmental Quality, William Holbrook, yesterday. The council’s chairman is the senior environmental adviser to the president, James L. Connaughton.

A State Department official, speaking on condition of anonymity, said ratifying the treaty would permit the American government to nominate members to bodies that interpret and enforce it, such as the Law of the Sea Tribunal and the Continental Shelf Commission.

“Having U.S. members on those bodies would help ensure the convention is being interpreted and applied in a manner consistent with the U.S. national security interest,” the official said. Becoming a party to the treaty would also help America “deflect potential proposals” that may conflict with its interests, particularly in the area of navigation, the official added.

Critics of the treaty say customary international law already governs international navigation. They say the treaty introduces ambiguities into law and hands decision-making to an international tribunal.

“The best way to protect your rights is good bilateral relationship with countries that have important straits and passages, and a powerful navy that protects your rights,” said Mr. Bandow, a senior fellow at the Cato Institute.

The State Department counters that customary law changes over time, depending on the behavior of countries, and that a treaty would guarantee “stability” to the law.

Mr. Lugar has said joining the treaty would help preserve American access to sea routes to oil regions, in the event that a country such as Indonesia moved to block access.

Although the treaty was renegotiated by the Clinton administration in the 1990s, its Cold War origins rankle many of its critics.

“It was a product of efforts by the Soviet Union and so-called “nonaligned” nations to redistribute the world’s wealth, in conformity with the socialist ‘New International Economic Order,'” Mr. Gaffney said.

While the Bush administration has been steadfast in its support for the treaty, critics hope congressional Republicans will make its defeat a priority, faced with the organized opposition from their own supporters.

“We’ve got enough right-wing heavy hitters to make some of them listen,” said Ian Walters, a spokesman for the American Conservative Union, which is organizing Friday’s anti-treaty event.