The FGM 148 Javelin is a US-manufactuered shoulder-launched missile created to destroy modern tanks by striking them from above, where their armour is thinnest.
"These weapons were for the protection of forces mission intelligence and counter-dismay missions", the defence ministry commentary talked about.
The ministry said in a statement that the Javeline missiles were "damaged and unusable" and claimed "the armaments were being temporarily stocked at a depot ahead of their destruction".
"They were not transferred to local forces", a statement from the ministry said.
The cache of four Javelin anti-tank missiles were discovered after forces loyal to the United Nations -backed government raided the camp in Gheryan, in the mountains south of Tripoli, on June 26, the New York Times earlier reported. "We expect all recipients of USA origin defense equipment to abide by their end-use obligations".More news: Tucker Carlson Calls 'Annoying' Ilhan Omar Proof Immigration Is 'Dangerous' To US
Al-Araby Al-Jadeed daily, citing Libyan and Egyptian sources, said large-scale troop mobilisation was underway across Egypt's western border and Libya's southern border, with funding from the United Arab Emirates (UAE) and Saudi Arabia. It is not clear how the weapons ended up under the control of Haftar's LNA militia.
Meanwhile, the GNA has its like supporters, including Turkey and Qatar.
More than 1,000 people have died in the fighting since Haftar launched his offensive on Tripoli, including scores killed in an air strike that hit a detention centre for migrants.
France broadly supports Haftar, regarding his forces as helpful in the fight against Islamist militants.More news: UK MPs back same-sex marriage and abortion laws for Northern Ireland
France has technically taken a mediation role within the conflict. "However, there are suspicions they back Gen Haftar".
France said on Wednesday that the anti-tank missiles were never intended for sale or transfer to any party to Libya's conflict, which would violate the sales agreement with the United States as well as a U.N. arms embargo. French forces deployed in Libya have largely been based in the east, far from Tripoli near where the base was located.
Libya has remained beset by turmoil since 2011 when a NATO-backed uprising led to the ouster and death of long-serving President Muammar Gaddafi after more than four decades in power.
Human rights groups have accused the LNA of war crimes against civilians.More news: Billionaire Ross Perot Dies Aged 89