U.S. Secretary of State John Kerry told Russia’s foreign minister, Sergei V. Lavrov, that the United States was deeply concerned about reports that the Kremlin may be planning to vastly expand its military support for President Bashar al-Assad of Syria.
Kerry warned that such a move might even lead to a “confrontation” with the American-led coalition, according to the State Department.
The conversation between the two also covered concerns that the United States had about reports that suggest an imminent Russian military buildup in Syria.
A statement released by the State Department said, “The secretary made clear that if such reports were accurate, these actions could further escalate the conflict, lead to greater loss of innocent life, increase refugee flows and risk confrontation with the anti-ISIL Coalition operating in Syria.”
The State Department didn’t specify if Mr. Lavrov responded to Mr. Kerry’s concerns or provided any indication of Russia’s intentions. The statement did note that the two men planned to continue their discussion when the United Nations General Assembly meets later this month.

According to a New York Times report, Russia has sent a military team to Syria and has transported prefabricated housing units for hundreds of people to an airfield near Latakia. Russia has also set up an air traffic control tower and requested the rights to fly over neighboring countries with military cargo aircraft in September.
American officials have acknowledged that they don’t know what Russia’s intentions are, but they say the airfield could be used to transport military supplies for the Assad government or to launch airstrikes to help the Syrian troops.
According to American officials, the housing units the Russians have in Syria could accommodate as many as 1,000 Russian military advisers and other personnel.
A coalition led by the United States has been bombing Islamic State positions in Syria. The United States and Turkey have also been conducting airstrikes along the northern border of Turkey and Syria in an attempt to remove ISIS militants from the area.
The warning from the State Department that a major Russian deployment might “risk confrontation,” pointed to the fact that the Russian airstrikes might interfere with the airstrikes that the United States and its partners are carrying out in Syria.
There is also the possibility that Russian aircraft or Russian-backed Syrian government forces might attack opposition groups the Unites States and its allies are supporting.
The moves by the Russian government come as Mr. Kerry has been trying to convince Russia’s President, Vladimir Putin, to work with the United States on a political solution to the bloody conflict in Syria.