Damascus, Aug 1 : UN special envoy for Syria Geir O. Pedersen has called for upholding the principle of the protection of civilians and international humanitarian law, a spokesman for the world body has said. The spokesman, said in a statement issued on Saturday on behalf of the envoy, that Pedersen "is following with great concern the developments in the southwest of Syria", reports Xinhua news agency. "He is actively in contact with relevant parties to ensure that violence ceases and is calling on all to de-escalate. "He underlined to all that the principle of the protection of civilians and international humanitarian law must be upheld," said the spokesman. "The special envoy emphasizes the humanitarian dimension of the situation, recalling the messages he received from people in Daraa stating they did not want to leave their homes," he added. "The special envoy notes that this uptick in tension in the southwest illustrates the need for all in Syria to agree on a nationwide ceasefire, in line with Security Council Resolution 2254 (2015)," the spokesman added. /IANS