The head of a Syrian opposition-run rescue group on Tuesday denounced a UN decision to give Syrian President Bashar al-Assad authorization over aid deliveries through border crossings with Türkiye, saying it gave him "free political gain". UN Secretary-General Antonio Guterres said on Monday Assad had agreed to allow UN aid deliveries to opposition-held northwest Syria through two crossings on the border with Türkiye for three months. "This is shocking and we are at loss at how the UN is behaving," Raed al-Saleh, head of the rescue group known as the White Helmets, told Reuters. A UN spokesperson was not immediately available for comment on the complaint. The opposition-held enclave in northwest Syria was devastated by a 7.8 magnitude earthquake and powerful aftershocks on Feb. 6, which killed more than 37,000 people in Türkiye and Syria. The White Helmets, famous for rescuing people trapped in bombed buildings during Syria's more than 10-year war, said the death toll from the earthquake in the northwest was 2,274. Many residents of the region were already displaced by Russian and Syrian bombing in the course of the war. Rescuers and aid groups have complained about the slow delivery of aid after the earthquake. UN officials have acknowledged aid was slow initially but said they were stepping up deliveries, including getting supplies from Türkiye. Large deliveries of aid from Saudi Arabia and Qatar have begun arriving in the opposition-held enclave ahead of UN deliveries, Saleh said. "They will make a big difference because they are entering directly," he said. Later on Tuesday, Saleh said the search operations for survivors are about to end. "It's about to come to a close. The indications we have are that there are not any (survivors) but we are trying to do our final checks and on all sites," he stated. The group said they were also collecting names of the missing people in the enclave.