This is not the first time the Russian government has expressed such views in recent weeks. Russia seemingly feels the U.S. military has no purpose in Syria now that the the Islamic State militant group (ISIS) has largely lost its foothold in Syria and Iraq. The envoy's remarks also come after the U.S. and Russia have sparred over airspace in Syria. In mid-December, two U.S. warplanes in Syria were diverted from supporting ground operations against ISIS to intercept Russian fighter jets that allegedly crossed into U.S. coalition airspace. But the Pentagon has signified it has no plans to withdraw U.S. troops from Syria any time in the near future. "We are going to maintain our commitment on the ground as long as we need to, to support our partners and prevent the return of terrorist groups," Pentagon spokesperson Eric Pahon told Agence France-Presse earlier this month. "To ensure an enduring defeat of ISIS, the coalition must ensure it cannot regenerate, reclaim lost ground or plot external attacks," he added. There are currently nearly 2,000 U.S. troops in Syria, according to numbers from the Pentagon. Since the Syrian conflict began in 2011, it has claimed more than 400,000 lives, according to the U.N., and contributed to the worst refugee crisis since World War II.