In a CNN interview marking the tenth anniversary of President Ronald Reagan's bombing of the Libyan capital, Col Gaddafi denied that the site, inside a hill at Tarhuna, 35 miles the capital, was being developed as a secret, well-nigh invulnerable site to manufacture chemical and biological weapons.
The US had produced no concrete evidence to support its claims, he said. None the less, Libya was ready to permit international experts to examine the site, albeit under certain conditions which Col Gaddafi would not specify.
But such equivocation will not satisfy Washington which, despite some scepticism from allies including Egypt and France, has gone to unusual lengths to single out Tarhuna as a menace to global security - complete with a warning by William Perry, Defense Secretary, that the US was prepared to attack the plant if necessary to prevent its completion. This is likely within 12 to 18 months, according to intelligence estimates here.
Although Pentagon officials say the US will first seek to halt the plant by diplomatic means, they leave no doubt that the military threat is real. Countering claims that, short of nuclear weapons, the Pentagon had no means of knocking out so well protected a target, they point to ground- penetrating bombs like the 5,000lb GBU-28, said to be capable of piercing 100ft of soil or concrete 22ft thick.
Washington, moreover, has attacked Libya before, as the setting of the interview underlined. The Libyan leader spoke in the ruins of his house destroyed when F-111s bombed Tripoli on 16 April 1986, in reprisal for an attack at a Berlin nightclub which killed two US soldiers. Mr Reagan said the US had firm evidence of "direct" Libyan responsibility.
More details of Tarhuna emerged at a Pentagon briefing last week on chemical- weapons proliferation, including an artist's impression of the site based on satellite photos. It shows a partially excavated and terraced desert hillside, with roads leading to tunnels bored into the foot of the mountain.
Once complete, officials say, Tarhuna will be able to produce 110 tons of poison and nerve gases over three years, as much as at Rabta, a previous suspected Libyan chemical-weapons plant that was closed after a fire in 1990. "We have absolutely no doubt ... the new facility is intended to make chemical weapons," Patrick Hughes, head of the Defense Intelligence Agency, said.
But domestic politics also play a part. Anxious to fend off Republican criticism that he is neglecting defence, Mr Clinton wants to show his administration is responding to the new challenges of a post-Cold War world, above all to the threat posed by proliferation of weapons of mass destruction.
Even so, Col Gaddafi spoke almost warmly of him in the interview, calling Mr Clinton "a man of peace", unlike his predecessors in the White House.