Libya was operating a more advanced and longer-running program to develop nuclear weapons than outside intelligence agencies and nuclear watchdogs had imagined, according to a confidential report Friday by the United Nations' nuclear watchdog.
The analysis by the International Atomic Energy Agency, or IAEA, showed that Libya's program dated to the early 1980s and had succeeded in producing a small amount of plutonium and assembling the basic components to enrich uranium for a nuclear weapon.
Libya announced in December that it was abandoning its nuclear weapons program after months of secret negotiations with the United States and Britain. As part of its decision, Libya opened its nuclear sites to inspectors from the IAEA.
Libya has acknowledged obtaining much of its nuclear technology, including designs for a nuclear warhead, from a network headed by Pakistani scientist Abdul Qadeer Khan.
"It is evident already that a network has existed whereby actual technological know-how originates from one source, while the delivery of equipment and some of the materials have taken place through intermediaries," the report said.
The report said that some suppliers in the network were unaware of the destination for their equipment and that others must have known because they had removed serial numbers from material.
But the IAEA report made it clear that Libya's nuclear ambitions existed before its contact with Khan in the mid-1990s and extended beyond the global network he assembled.
Information provided to the U.N. agency by Libyan officials showed that work started on a nuclear program in the early 1980s and that the country purchased a considerable amount of equipment overseas.
Jon B. Wolfsthal, a nuclear expert at the Carnegie Endowment for International Peace, said in a telephone interview that he was shocked by the length of time Libya had been operating a secret weapons program.
"We knew that Libya had an interest in nuclear technology, but the duration and the depth of it is surprising," he said. "The other thing is the sheer size of what they were trying to acquire."
The report said Libya ordered 10,000 advanced uranium centrifuges, which are used to convert uranium into fissile material for nuclear weapons.
Although the IAEA did not identify the source of the centrifuges, Libya acknowledged earlier that it had tried to buy them from Khan.
The IAEA director-general, Mohamed ElBaradei, issued the 10-page report Friday night to members of the agency's governing board. A copy of the report was provided to The Times.
Malaysian authorities also released a report dealing with Libya's nuclear program Friday. Based on information provided by one of Khan's middlemen who was involved with a Malaysian company, the report outlined nuclear technology sent to the North African country from the late 1990s to last year by suppliers in Pakistan, Turkey, Britain, Switzerland, Germany and Malaysia.
Some names had surfaced earlier in the inquiry, but the Malaysian report was the first to name Turkish companies. Two Turkish businessmen were reported to have supplied electronics, aluminum casings and electrical cabinets for Libya's centrifuge program.
Details about the plan to enrich uranium for bombs through centrifuges had surfaced in recent weeks, but information about the plutonium extraction was kept secret until the IAEA report.
Libya managed to separate very small quantities of plutonium from spent reactor fuel from a research reactor between 1984 and 1990 while the reactor was being monitored by the IAEA, according to the report.
Like enriched uranium, plutonium can be used to make an atomic weapon. The report said that the quantity of plutonium was far less than the amount needed for a weapon and that no uranium had been enriched.
Libya was the third country known to have diverted plutonium from a reactor despite IAEA safeguards. Iraq managed to do so before the 1991 Persian Gulf War, and North Korea also secretly transferred plutonium to a separation facility while IAEA inspectors were monitoring its nuclear plants.
Libya is a signatory to the Nuclear Nonproliferation Treaty and is required to report its nuclear activities to the IAEA. But ElBaradei said he would not recommend referring the violations to the U.N. Security Council because of Libya's cooperation since December.
A Western diplomat said he did not expect the U.S. to push for referring the matter to the Security Council for possible sanctions.