The Director-General of the International Atomic Energy Agency, Mr Mohamed ElBaradei, is on his way to Libya to inspect nuclear facilities following this week's agreement between it, the US and Britain.
Mr ElBaredei, flying to Tripoli from IAEA headquarters in Vienna, said there were no signs Libya had enriched uranium - a step that, were it taken, could be the first move to a bomb.
"From the look of it, they were not close to a weapon, but we need to go and see it and discuss the details with them," he said in an interview with Reuters today.
"The important thing for me is to get a comprehensive understanding of the programme - the origin, its history, its extent, and then agree with the Libyan authorities on a plan of action to eliminate whatever needs to be eliminated that is not linked to peaceful activities."
Libyan leader Muammar Gaddafi's oil-rich state, long on the US list of sponsors of terrorism, now wants trading benefits, including an end to US sanctions for his promise to abandon weapons of mass destruction.
Libya's moves to scrap its illicit weapons programmes mark an about-face for the mercurial Gaddafi, who seized power 34 years ago in the desert nation of 5.5 million.
ElBaradei could begin talks with senior Libyan officials as early as Saturday afternoon.
Vienna-based diplomats who watch the IAEA said they believed ElBaradei would meet Gaddafi, who has pledged to let U.N. experts assess and dismantle banned weapons projects.