Russian lawmakers voted unanimously today to let President Vladimir Putin send Russian troops to Syria.
The Kremlin sought to play down the decision, saying it will only use its air force there, not ground troops.
Putin has to request parliamentary approval for any use of Russian troops abroad, according to the constitution. The last time he did so was before Russia annexed Ukraine's Crimean Peninsula in March 2014.
The Federation Council, the upper chamber of the Russian parliament, discussed Putin's request for the authorisation behind closed doors today.
Sergei Ivanov, chief of Putin's administration, said in televised remarks after the discussion that the parliament voted unanimously to give the green light to Putin's plea. The proposal does not need to go to another legislative body.
Ivanov insisted that Moscow is not going to send ground troops to Syria but will only use its air force "in order to support the government Syrian forces in their fight against the Islamic State" group.
Ivanov told reporters that Russia decided to help Syrian President Bashar Assad in order to protect its own country from Islamic militants, not because of "some foreign policy goals or ambitions that our Western partners often accuse us of."
"We are talking about Russia's national security interests," Ivanov said, adding that that Moscow is worried about a growing number of Russian recruits going off to fight for the Islamic State group.
Ivanov said thousands of Russians had gone off to fight in Syria so it would be wise for Moscow to "take pre-emptive steps and do it on the distant frontiers instead of facing the issue here and later on."
Putin's request comes after his bilateral meeting Monday with President Barack Obama on the sidelines of the United Nations General Assembly meeting in New York, where the two were discussing Russia's recent military buildup in Syria.
Ivanov said the motion comes after Moscow received a request from Assad asking for help.
He said the biggest difference between other countries conducting air strikes in Syria -- such as the US -- is that "they do not comply with the international law, but we do."
Moscow has always been a top ally for Assad. The war in Syria, which began in 2011, has left at least 250,000 dead and forced millions to flee the country. It is also the driving force behind the record-breaking number of asylum-seekers fleeing to Europe this year.
