The United Nations announced on Thursday that the humanitarian situation in Syria has reached the lowest point since the organization launched its humanitarian task force in 2015. The force has been unable to make deliveries to desperate Syrians for the past two months as the Syrian regime has withheld approval for aid convoys, said UN humanitarian adviser Jan Egeland on Thursday. Before they can move into besieged areas or across front lines, the convoys require letters from the regime and security guarantees from armed groups. “It’s an all-time low in giving us the facilitation letters,” Egeland told reporters after meeting senior diplomats in Geneva. Egeland called on Russia, Turkey and Iran to de-escalate the fighting in Idlib governorate, which he said was “screaming for a ceasefire”. “When we need their ability to influence the parties the most, in this bleak hour for humanitarian work, humanitarian diplomacy seems to be totally impotent. We’re getting nowhere at the moment.” Last week, a ceasefire was agreed over the rebel-held Eastern Ghouta region, a Damascus suburb. The agreement was reached between Russia and the opposition High Negotiations Committee in order to allow aid to reach the regime-besieged enclave. It was however not respect as attacks have continued against the region. Meanwhile, the opposition in the rebel-held Damascus suburb of Douma accused the regime of carrying out on Thursday a gas attack against residential areas, the third such assault in less than a month. Rescue workers in Douma reported what they described as a suspected chlorine gas attack that injured a number of civilians. The opposition-run Ghouta Media Center reported in a posting on its Facebook page that three people were killed and dozens suffered shortness of breath as a result of surface-to-surface missiles, some of them carrying chlorine gas. The accounts followed a suspected attack in late January near Damascus that activists and rescue teams said affected nearly 20 civilians.