MOSCOW (Reuters) - President Vladimir Putin said on Friday Russia is supporting the opposition Free Syrian Army, providing it with air cover, arms and ammunition in joint operations with Syrian troops against Islamist militants.

His statement appeared to be the first time Moscow said it was actually supporting Syrian President Bashar al-Assad’s opponents in the fight against Islamic State forces. Putin said last month the Russian air force had hit several “terrorist” targets identified by the Free Syrian Army.

A few hours later, Kremlin spokesman Dmitry Peskov told reporters that Putin had been talking about weapons supplies to the armed forces loyal to Assad.

But Peskov did not say Putin had been mistaken or misquoted about supplies to the Free Syrian Army and did not deny weapons were going to the opposition force.

Western and Arab states carrying out air strikes against Islamic State for more than a year say that Russian jets have mainly hit other rebel forces in the west of Syria.

Asked about Putin’s remarks at a briefing, U.S. State Department spokesman John Kirby said it was “unclear to us ... whether these claims of support to the FSA are true” and noted that “the vast majority” of Russian air strikes had targeted groups opposed to Assad.

British Defense Secretary Michael Fallon, speaking at a Pentagon news conference after talks with his U.S. counterpart, said Russia “began by bombing the Free Syrian Army” and it was “welcome” news if they were now supporting them.

“What they’ve got to do is stop propping up the Assad regime, stop bombing opposition groups who are opposed to the Assad regime ... and get behind the political process that is now under way of leading that country to a more pluralist government and a future without Assad,” he said.

Putin told an annual meeting at the Russian defense ministry that on Friday Russian planes were assisting “in uniting the efforts of government troops and the Free Syrian Army”.

“Now several of its units numbering over 5,000 troops are engaged in offensive actions against terrorists, alongside regular forces, in the provinces of Homs, Hama, Aleppo and Raqqa,” he said, referring to the Free Syrian Army.

“We support it from the air, as well as the Syrian army, we assist them with weapons, ammunition and provide material support.”

When asked if Putin had been speaking about the Free Syrian Army, Peskov replied: “Please do not cling to meanings in this case. Such an interpretation is possible.”

“Russia supplies weapons to the legitimate authorities of the Syrian Arab Republic,” he said.

Russian President Vladimir Putin addresses the audience during an annual meeting at the Defence Ministry in Moscow, Russia, December 11, 2015. REUTERS/ Alexei Druzhinin/Sputnik/Kremlin

Putin said strikes by Russia’s air force and navy had inflicted heavy damage on the infrastructure of Islamic State, which controls large areas of eastern Syria and western Iraq.

Defense Minister Sergei Shoigu said, however, that the influence of Islamic State was increasing in Syria, where militants control roughly 70 percent of the country.

The number of Islamic State fighters in Iraq and Syria is about 60,000, Shoigu said, and there is a threat of violence spilling over into post-Soviet Central Asia and the Caucasus.

Talking to his generals, Putin issued a veiled warning to Turkey, whose downing of a Russian bomber jet near the Syrian-Turkish border last month sent bilateral relations to a freezing point and led Moscow to impose economic sanctions to Istanbul.

“I want to warn those who may again try to stage provocations against our troops,” he said.

“I order you to act in an extremely tough way. Any targets threatening Russia’s (military) group or our land infrastructure must be immediately destroyed,” Putin told the generals.

Turkish Foreign Minister Mevlut Cavusoglu on Friday called on Russia for calm, but said Turkey’s patience is not unlimited.