Russia's state-run arms exporter has lost a total of $4 billion over the cancellation of contracts with Libya, Rosoboronexport head Anatoly Isaikin said on Wednesday.
The figure includes losses of opportunity and foregone profits, he added.
Isaikin stressed that in accordance with international agreements, Russia is currently not supplying any arms to Libya.
Russia has joined the arms sanctions against Libya, suspending all contracts for the supply of military hardware to the country.
Russian President Dmitry Medvedev on Friday gave his backing to a UN Security Council resolution which authorized international military action in Libya.
UN Resolution 1973, which Russia abstained from voting on in March, authorizes a no-fly zone over Libya and the use of "all necessary measures" to protect Libyan civilians.
Thousands of people have been killed since the uprising against Gaddafi's rule began in February.
