The weapons included handguns, grenades and bomb-making materials and were shipped using the diplomatic bag. They may have been intended for use in assassinations on Libyan dissidents abroad, or for operations against the embassies' host countries.
The scale of the scheme is emerging for the first time now as the leadership installed in last year's rebellion against Gaddafi takes over control of embassies and finds the arms, said Mohammed Abdul Aziz, Libya's deputy foreign minister.
Gaddafi's officials shipped weapons to "many countries. In Africa, in Asia, in Europe. So it's not only in two or three countries," Abdul Aziz told Reuters in an interview.
"Nobody knows what was the plan. Was it to address certain problems as far as the host country is concerned? Was it going to be used against Libyan nationals? Nobody knows," he said. "Honestly, everything is possible with the previous regime."
Asked if the weapons were concealed in Libyan embassies as part of a concerted operation conceived inside Gaddafi's administration, Abdul Aziz said: "I have no single doubt in my mind. No single doubt."
During his 42 years in power, Gaddafi was frequently accused of exporting violence.
The 1988 bombing of a U.S. airliner over the Scottish town of Lockerbie, and the 1984 shooting of British policewoman Yvonne Fletcher outside the Libyan embassy in London, are some of the most high-profile cases.
The fact that Gaddafi's officials were keeping weapons inside Libyan embassies as late as last year suggests he was still plotting killings abroad, even after he renounced violence in the 1990s and Western states restored diplomatic relations.
GUN BARREL DIPLOMACY
In the past six months, as Gaddafi loyalists lost control over foreign embassies, weapons discoveries have been reported in missions in the capitals of Greece, Egypt and Morocco.
Local media reports said the Athens find, in February, included 30 handguns, two sub-machineguns, 15 kg of plastic explosives, detonators, two hand grenades, silencers and wiretapping equipment.
The weapons uncovered in Rabat included booby-trapped vehicles and rocket-propelled grenades, a Moroccan newspaper reported.
The deputy foreign minister said the finds announced so far were only the tip of the iceberg, though he said he could not give a list of the countries where Libyan embassies had weapons caches.
He said he did not believe weapons were found in the mission in the United States, but that they were discovered in embassies in European Union states besides Greece, as well as on other continents.
"We found a variety of weapons. You have pistols, you have hand grenades, you have chemical stuff ... to manufacture certain types of hand-made grenades, it's not chemical weapons, it's chemical stuff," he said.
He said Libyan embassies which had discovered weapons on their premises were negotiating arrangements with host country governments to either surrender the arms to them or to have them returned by legal means to Libya.
"There are countries who accepted the idea of accepting those weapons, we have still some embassies that we have to strike an agreement with the host government," said Abdul Aziz.
"We are very transparent, we have nothing to hide at the moment, but the fact remains that there are some weapons."
Under the Vienna Convention, the international treaty which governs diplomatic missions, governments have little leeway for stopping foreign embassies concealing weapons.
A host state does not have the right to search an embassy's premises. The treaty states that goods sent to and from the embassy by diplomatic bag must contain only documents or items for official use, but the packages are exempt from being searched or detained.
(Additional reporting by Souhail Karam in Rabat; Editing by Maria Golovnina)
