The United States will tell the United Nations this week it is renouncing formal involvement in a treaty creating the first permanent war crimes tribunal, Secretary of State Colin Powell said Sunday.

Powell said the Bush administration will notify U.N. Secretary-General Kofi Annan that the United States has no intention of ratifying the treaty and now considers itself "no longer bound in any way to its purpose and objective," Powell said on ABC's "This Week."

The International Criminal Court gained the necessary international backing to come into being when 10 nations joined 56 others last month in announcing their ratification of the treaty negotiated in Rome in 1998. President Clinton signed the treaty, but never submitted it to the Senate for ratification. The Bush administration has made its opposition clear.

A senior administration official, speaking on condition of anonymity, said Saturday that that opposition was expected to be formalized Monday in a speech by Under Secretary of State Marc Grossman and at news briefing by Pierre-Richard Prosper, the State Department's ambassador for war crimes issues.

The United States fears the impact on American citizens, arguing that safeguards against frivolous or politically motivated prosecutions of U.S. soldiers and officials are not sufficient.

The court, to be formed this summer without U.S. participation, will fill a gap in the international justice system first recognized by the U.N. General Assembly in 1948 after the Nuremberg and Tokyo trials for World War II's German and Japanese war criminals.

Tribunals have been created for special situations -- like the 1994 Rwanda genocide and war crimes in former Yugoslavia -- but no mechanism existed to hold individuals criminally responsible for serious crimes such as genocide.

"We are the leader in the world with respect to bringing people to justice," Powell said. "But ... we found that this was not a situation that we believed was appropriate for our men and women in the armed forces or our diplomats and political leaders."