Washington ? Nearly three months after the successful operation, the Bush administration confirmed on Wednesday interception of an illegal shipment of thousands of parts of uranium-enrichment equipment bound for Libya.

A senior State Department official, John R. Bolton, plans to fly today to London to make plans with Britain for holding Moammar Gadhafi to his pledge to dismantle his nuclear weapons program.

There is an extensive black market that provided Libya with tens of millions of dollars in equipment, but there now is an aggressive program of interdicting delivery and the administration intends to pursue middlemen actively, U.S. official said.

The seizure in early October was just the tip of the iceberg in the spread of dangerous equipment to rogue-states, but it sealed Gadhafi’s decision to announce on Dec. 19 he was dismantling the expensive program, said the official on condition of anonymity.

The intercepted parts were being delivered to Libya on a German-owned freighter that was diverted to an Italian port.

The United States and Britain plan to send experts to Libya in January to analyze the extent of Libya’s nuclear program and its quest for biological and chemical weapons as well as modern missiles.

Top Bush administration officials are convinced the programs are far more extensive than outlined by the International Atomic Energy Agency and said this week that the United States and Britain would pursue their own joint program to uncover Libya’s operation and hold Gadhafi to his promise to uproot development of nuclear, biological and chemical weapons as well as potent missiles.

The interception of centrifuge parts bound for Libya was first reported in Wednesday’s Wall Street Journal. The White House and State Department then confirmed the report with few details and no explanation why confirmation took nearly three months.

The director of the International Atomic Energy Agency, Mohamed ElBaradei, told The Associated Press Tuesday he did not want American or British help on the ground in Libya.

“As far as I’m concerned, we have the mandate, and we intend to do it alone,” ElBaradei said.

But senior American officials confirmed an active U.S. and British role and said Libya’s programs were far more extensive than the U.N. agency had disclosed. “The IAEA is in there because of what we uncovered,” said one U.S. official on condition of anonymity. “The Libyans came to us and the British.”