United Nations weapons inspectors have begun visiting sites in Libya related to the country's nuclear weapons program.

A spokesman for the International Atomic Energy Agency says inspectors saw four previously unvisited Libyan nuclear sites Sunday.

Led by the head of the International Atomic Energy Agency, Mohammed ElBaradei, U.N. weapons inspectors are to begin a tour of Libya, following the country's recent announcement that it had been attempting to build banned weapons of mass destruction, including nuclear weapons.

A team of international weapons inspectors arrived in Tripoli Saturday and, according to Libya's Foreign Ministry, they will be shown weapon-development sites, including centrifuges for uranium enrichment.

Enriched uranium can be used in nuclear-powered generators and for the production of nuclear weapons. The inspectors are also interested to learn where Libya acquired the centrifuge technology.

Mr. ElBaradei is expected to stay in Tripoli until Monday, and may meet with Libyan leader Moammar Gadhafi.

The remaining inspectors will reportedly remain in the Libyan capital until Thursday, while conducting inspections of the country's weapons programs.

More than a week ago, Libya announced that it had attempted to build banned weapons but was scrapping its effort and would sign the Additional Protocol of the Nuclear Non-Proliferation Treaty allowing for more stringent and unannounced inspections of its weapons facilities.

While Libya remains on the State Department's list of countries that sponsor terrorism, President Bush applauded Tripoli's decision to end its effort to build weapons of mass destruction.