Moscow: Russia’s Foreign Ministry said on Wednesday that Russian military experts were present in Syria, the first official confirmation that the Russian military is on the ground in Syria after weeks of increased talk that Moscow may be growing its presence there. Maria Zakharova, a spokeswoman for the Foreign Ministry, said the experts were assisting with Russian arms deliveries to Syria which Moscow says are aimed at ‘combating terrorism’.

Moscow said it was ready to look at “additional measures” to fight Islamist insurgents in Syria if the situation worsens, according to the Foreign Ministry.

“If additional measures to step up the anti-terrorist fight are required, Russia is ready to consider them, but only in strict compliance with international and Russian law,” Zakharova told reporters in Moscow. The possibility is “hypothetical” and “the situation now doesn’t require it,” she said.

The US administration has criticized Russia for suspected deployment of additional military personnel and aircraft in Syria, saying the move could trigger an escalation of the four- year long conflict.

While Russian has sent advisers to help the Syrian army, reports of a military buildup in Syria are designed to foster “hysteria,” Zakharova said.

“Russia has never made a secret out of its military cooperation with Syria,” Zakharova said. “Russian specialists are helping Syrians to use Russian equipment. It’s difficult to understand the anti-Russian hysteria in this regard.”

Russia, under US and European sanctions for its support of separatists in Ukraine, has been at the centre of a burst of diplomatic activity aimed at brokering a deal to resolve the Syrian conflict.

Russia has been holding talks on a political settlement in Syria with Saudi Arabia and the US, which have supported rebels seeking Syrian President Bashar Al Assad’s ouster, as well as Iran, which backs Al Assad, and other key Arab states. The Kremlin has refused demands for the immediate removal of Al Assad, a long-time ally.

Russia has increased shipments of munitions, weapons and fuel to Syria since the beginning of August, Vedomosti reported, citing unidentified military officials. Flights will have to cross Iran and Iraq after Bulgaria closed airspace to Russia, the newspaper said. However, on Wednesday Bulgaria said it would allow Russian supply flights to Syria to use its airspace if Moscow agrees to checks of their cargo at a Bulgarian airport.

“If our Russian colleagues agree these flights to be checked at a Bulgarian airport we will issue such a permission,” Mitov told reporters. On Wednesday the Russian Foreign Ministry said the United States’ requests to Greece and Bulgaria to close their airspace for Russian flights to Syria amounted to “international boorishness”.