GENEVA, March 1 (Xinhua) -- The United Nations will not cease asking for full implementation of UN Security Council Resolution 2401 which calls for a 30-day ceasefire in Syria, UN Special Envoy for Syria Staffan de Mistura said Thursday.

"We will continue asking until we are blue in the face for both sides...because there has been on both sides shelling, not comparable in terms of proportion but there has been from both sides...and for convoys to be allowed to get to Eastern Ghouta in particular" said the UN envoy speaking to the media here.

The UN Security Council passed a unanimous resolution on Feb. 24 calling for a 30-day countrywide cease-fire, but it has not come into effect.

Russian Foreign Minister Sergei Lavrov had told the UN Human Rights Council on Wednesday that militants and their sponsors are preventing the delivery of humanitarian aid and evacuation of civilians in Eastern Ghouta.

De Mistura said the UN continues working on UN Security Council 2254 that seeks to bring an end to the seven-year conflict in Syria, but that "the priority needs to be stopping the suffering and the tragedy of the civilians in Eastern Ghouta and elsewhere."

UN special advisor on humanitarian affairs Jan Egeland told journalists that the message to 23-member states of the Humanitarian Task Force on Syria in Geneva on Thursday was "You are failing to help us help civilians in Syria."

He said he knew of no other place that "even close to having so many children, families, innocent people being displaced, fleeing for their lives, being killed, being maimed."

Egeland said Syria is unique in that it is a place "where parties have for a very long time specialized in denying humanitarian access to these civilians."

He said the United Nations is again calling on Russia, the United States and countries who have influence in Eastern Ghouta to help the UN getting several convoys a week to reach all places in Eastern Ghouta, to get over 1,000 priority medical cases evacuated from there.