MOSCOW, June 21 (Xinhua) -- Russian aircraft have dropped 17 tons of UN humanitarian aid on Syria's eastern city of Deir ez-Zor, which had been besieged by Islamic States (IS) militants, the Russian Center for Reconciliation of Opposing Sides said on Tuesday.

The aid, which was delivered via parachutes, contains grain and food products.

Kafr Batna, a suburb of Damascus, has also received 41 heavy truckloads of humanitarian aid, including food and medicines.

A cease-fire brokered by Russia and the United States, which took effect in February, has brought relative calm to the war-ravaged country. The cessation of hostilities does not apply to terrorist organizations, such as the IS.