Russia has signed deals with Syria under which it will sell it warplanes, anti-tank weapons and air defense systems, Itar-Tass news agency quoted a senior Russian arms trader as saying on Friday.
Mikhail Dmitriyev, head of the Federal Service for Military-Technical Cooperation, said Russia would supply Syria with MiG-29 fighters and truck-mounted Pantsir short-range surface-to-air missiles and anti-aircraft artillery systems.
He did not specify the kind of anti-tank weapons.
The arms deal is likely to be watched with unease by Syria's regional foe Israel and its ally the United States which imposed sanctions on Damascus for its support of militant groups and corruption.
Earlier this week, Russian President Dmitry Medvedev visited Syria -- the first visit to Damascus by a Moscow ruler since the 1917 Bolshevik revolution -- and oversaw talks on Russia's possible assistance in building a nuclear power plant in Syria.
While in Syria, Medvedev unnerved Israel by paying a visit to Khaled Meshaal, the exiled leader of the Palestinian Islamist group Hamas.
Israel's Foreign Ministry said it was "deeply disappointed" that Medvedev met the leader of Hamas, which it said was "a terror organization in every way."
A senior adviser to U.S. president Barack Obama said on Wednesday that Washington has made it clear to Russia that delivering an anti-aircraft system to Iran would have severe consequences for U.S. ties with Moscow.
Gary Samore, White House coordinator for arms control, weapons of mass destruction proliferation and terrorism, said he thought Russia understood Washington's position and would be surprised if Moscow shipped the S-300 anti-aircraft system that Iran has ordered.
"We've made it very clear to the Russians that that would have a very significant impact on our bilateral relations," said Samore. "I think the Russians understand that the consequences would be very severe."