The Kremlin also said President Vladimir Putin, chief ally of Syrian President Bashar al-Assad, talked on the telephone for the second time in five days with King Salman of Saudi Arabia, a country that has backed militant groups fighting the Damascus government.
Western powers have accused Russia of using its air force to bomb pro-Western groups such as FSA since it started its air strikes on Sept. 30, declaring a campaign against terrorism.
Foreign Ministry official Mikhail Bogdanov, answering a question on whether the Free Syrian Army group had visited Moscow last week, was quoted by Interfax news agency as saying: "Yes, they were here, including this (week) too," Reuters reported.
"They are here all the time, and those are different people, someone is leaving, someone is arriving, but they all say that they are the representatives of Free Syrian Army," he said.
Russia has shifted its position regarding Free Syrian Army, saying on Saturday that Russia's airforce, which has been bombing targets in Syria since Sept. 30, would be ready to help them, if it knew where they were.
The comments were aired days after Assad met Putin in Moscow to discuss a joint military campaign against militants in Syria.
Russia says the main aim of its military efforts, namely its air support for Syrian army, is to combat terrorism.