Libya is helping U.N. experts understand the shadowy international black market in weapons equipment and expertise, the nuclear agency chief said Tuesday.

Mohamed ElBaradei (search), director-general of the International Atomic Energy Agency (search), spoke after meeting with Libyan Foreign Minister Abdul Rahman Shalgam, at the end of two days of talks on the scrapping of Tripoli's nuclear arms program.

ElBaradei called his talks with Libyan officials "very helpful ... in providing information on routes of supply, extent (and) scope" of the black market chain.

He said he was leaving Libya with a better "understanding of parts of the puzzle that were not very clear to us before."

ElBaradei praised Libyan leader Moammar Gadhafi (search) and other officials for "complete openness and transparency" since the North African nation's decision in December to rid itself of its weapons of mass destruction programs.

"Part of that program has already been eliminated, and we still have some work to eliminate other parts that are less sensitive," ElBaradei said, speaking of the nuclear component.

He pledged his agency's support for peaceful Libyan nuclear programs in the field of agriculture and industry, once the last vestiges of military activity have been dismantled and removed.

Shalgam urged other nations in the region to follow Libya's example and use nuclear energy only "for the sake of prosperity and progress." While not naming any particular countries, his comments appeared directed at Israel, which has never acknowledged possessing nuclear weapons.

Libya was able to work for two decades on a secret nuclear arms program because of imports of black market technology and know-how.

During his visit, which shed light on the illicit network linking Europe, Asia, Africa and the Mideast, ElBaradei said new countries with illicit nuclear arms programs may be revealed through investigations by his agency and national intelligence services.

Libya, one of the key customers of the nuclear peddlers, has blown the whistle on the head of the network, Pakistani scientist Abdul Qadeer Khan, and more than a dozen of his middlemen.

ElBaradei said he believed Libya likely could be declared free of its nuclear weapons program by June.

"I think it is going very smoothly, very well, and the Libyans have confirmed again their full cooperation, their readiness to settle all the questions we have," he told reporters after meeting with Deputy Prime Minister Mating M. Mating, who heads Libya's nuclear activities.

However, some key elements of Libya's nuclear weapons program are still in place three months after its government pledged to scrap them, ElBaradei said. He did not elaborate, but another delegation member, speaking on condition of anonymity, said centrifuge equipment that can enrich uranium to weapons grade still remained assembled and in Libya.

Other equipment already has been shipped to the United States, which along with Britain negotiated the process that led in December to Libya's declaring its weapons programs — and its desire to scrap them. Also in the United States, under IAEA seal, are drawings of a 1960s nuclear warhead supplied by Khan's network.

Another delegation member said much of the investigative work into the nuclear supply chain would likely be wrapped up within three months. But ElBaradei cautioned of possible surprises ahead.

"We are still trying to understand the network, we are still trying to see whether other countries have received technology, have received weapons designs," he said. "We are putting the pieces of the puzzle together and trying to understand whether there is any additional work ... for us in the future."

"We are getting the names of more individuals, more companies," not only from Libya but "many different sources," ElBaradei said.