The U.S. administration is convinced that Libya's nuclear program was far more extensive than assumed by the U.N. International Atomic Energy Agency. So Washington has decided to send its own inspectors and British technical experts to Libya to help survey and dismantle weapons programs there.

But, although while it's happy to receive U.S. and British intelligence that will assist it, the IAEA doesn't want help on the ground.

U.S. Can't 'Do It Alone,' but U.N. Can?

"I am not familiar with anything they plan to do on a bilateral basis," IAEA Director General Mohamed ElBaradei said in an interview Tuesday, when asked about U.S. plans to police and scrap Libya's covert nuclear program. "But as far as I'm concerned, we have the mandate, and we intend to do it alone."

The conflict is in some ways similar to tensions between the agency and the White House over the extent of the nuclear weapons threat in Iraq under Saddam Hussein and in Iran.

The Americans went to war in March arguing that Saddam was trying to make nuclear and other weapons of mass destruction but have still not found such arms. ElBaradei maintains that what his teams saw in the months preceding the war suggested the Iraqis were in no position to build a nuclear weapon.

ElBaradei also disappointed the Americans on Iran. Though the United States asserts that uranium enrichment and other activities point to attempts to make nuclear weapons, a report by ElBaradei presented to the IAEA board of governors said there was "no evidence" of an arms program, despite an array of suspicious findings.

ElBaradei spoke after returning from a visit to Libya, where he and an IAEA team say four formerly secret nuclear sites in the capital, Tripoli. They said that, from what they saw, Libya was still years away from developing nuclear weapons.

ElBaradei also met with Libyan leader Moammar Gadhafi, who earlier this month admitted his country had been trying to develop weapons of mass destruction and agreed to let the IAEA monitor the dismantling of the programs.