Iran's Defense Ministry and The Aerospace Industries Organization filed the lawsuit against Russia's state-run arms export company Rosoboronexport in an international arbitration court in Geneva in April 2011, RIA Novosti reported.
"The lawsuit is being considered by an arbitration court in Geneva and, unfortunately, our chances to win the case are very slim," Russian Technologies Chief Executive Officer Sergei Chemezov said Thursday. "We are trying to agree an amicable settlement with Iran but no progress has been made so far."
Russia signed an $800 million arms contract with Iran at the end of 2007. Russia was to supply Tehran with five S-300PMU-1 missile defense system battalions.
However, in September 2010, Russian President Dmitry Medvedev issued a decree that canceled the deal in accordance with U.N. Security Council Resolution 1929, which bans supplying Iran with conventional weapons.
Iran has argued that the S-300 surface-to-air missile systems don't fall under the U.N. resolution because they are considered defensive weapons.