"The illegal annexation of Crimea by Russia, that did not get an immediate powerful response from the international community, has pushed the Kremlin to another step. [] Today the so-called 'green men' are landing in Syria, instigating the growth of violence in the Middle East and provoking a further increase in the number of refugees going to the EU," Poroshenko said at the annual Yalta European Strategy (YES) meeting in Kyiv on Friday. Russian Foreign Minister Sergei Lavrov told a briefing on Thursday that Russian military specialists have been present in Syria for years. Asked by a journalist whether there are Russian military servicemen in the Syrian Arab Republic's territory, Lavrov replied: "There are Russian servicemen in Syria, and they have been there for many years. Their presence there is related to the supplies of weapons for the Syrian army, which is bearing the principal burden of the opposition to terrorism represented by ISIS and other extremist groups." The Russian servicemen are present in Syria "to help the Syrians master hardware and prepare them for operations in the combat against terrorism," he said.