TEHRAN (Press Shia) – UN Secretary-General Antonio Guterres is following closely the latest escalation of hostilities in Syria and reminding all parties to the conflict that they have to adhere to the international law, Stephane Dujarric, the spokesman for the UN chief, said in a statement.

"The Secretary-General is following closely the alarming military escalation throughout Syria and the dangerous spillover across its borders. The latest events come as the Syrian people suffer through one of the most violent periods in nearly seven years of conflict. Over 1,000 civilian casualties from airstrikes were reported in the first week of February alone," the statement issued on Saturday said.

According to Dujarric, the UN chief is reminding all parties to the conflict that they must "abide by international law and relevant Security Council resolutions."

"The Secretary-General further calls on the parties to move swiftly toward a political solution, in line with Security Council Resolution 2254, which is the only way to end the violence and the terrible suffering of the Syrian people," the statement read, according to Sputnik.

His comments came after reports of downing of an Israeli warplane by the Syrian Arab Army.

An Israeli F-16 fighter jet was shot down by Syrian military on Saturday while targeting what it called Iranian sites responsible for launching a drone into occupied Golan Heights.

Pro-government military alliance in Syria said in a statement on Saturday that Israel would see a severe and serious response to its "terrorism" from now on.

The statement also said the drones -one of which Israel claims to have shot down- were being used against Daesh (ISIL) terrorist group.