The Syrian military used newly-arrived Russian warplanes to bombard Islamic State fighters in Aleppo province in northern Syria, a monitor said on Thursday.
Ground attacks accompanied the airstrikes, which began earlier this week, near the Kweiris Air Base in the eastern part of Aleppo province, the Britain-based Syrian Observatory for Human Rights said. Islamic State militants have surrounded Syrian government troops on the airbase for weeks.
Russia is helping Syria fight anti-government rebels with military aid that US officials say has included fighter jets, helicopter gunships, artillery, and ground forces. The first Russian drones were used against IS on Wednesday, reported Al Arabiya.
The Russian jets were being flown by Syrian pilots, said the Observatory, which tracks Syria's conflict through a network of sources on the ground. Syria's government confirmed on Tuesday that they received at least five fighter planes and additional reconnaissance aircraft from Russia. A Syrian military officer also told the Guardian that Russia was also providing satellite images of IS locations to aid with strikes.
Moscow's increased military support for President Bashar al-Assad has provoked alarm in the US and Western European countries, which oppose Assad. But the rise of a common enemy, the self-proclaimed Islamic State, has rendered divisions less clear, since the US is waging its own aerial campaign against IS militants in Syria and Iraq. Stronger Russian involvement in Syria means that forces of the former Cold War foes could encounter each other as they battle the same enemy.
During a meeting with the British Defense Secretary on Thursday, French Defence Minister Jean-Yves Le Drian said that France and Britain are concerned about a "very significant" increase in the Russian military presence in Syria.
Speaking on the sidelines of a conference on cybersecurity, British Defense Secretary Michael Fallon added that the issue would be discussed by the French and British foreign ministers "in a few hours' time" during talks on Syria being hosted in Paris.
Russia says Assad, its closest Middle East ally, should be part of international efforts to fight IS, while the US believes he is part of the problem.
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