The U.N. refugee agency said Tuesday that it is "extremely concerned" about the worsening humanitarian situation in eastern Ukraine with the civilian population there now lacking access to benefits and services previously provided by authorities. "Living conditions, particularly for those with damaged homes or sheltering in bunkers and basements under the rubble of their houses or apartment buildings, have been exacerbated by cold weather and low temperatures," Office of the U.N. High Commissioner for Refugees spokesman William Spindler said. "This has been further aggravated by restrictions to the movement of people and goods." According to Spindler, conditions in northern Donetsk and in Luhansk are particularly dire, with the supply of water and electricity often interrupted by shelling and rocket attacks. "The fighting makes the delivery of humanitarian aid to the many civilians trapped in the conflict areas extremely difficult. The scarcity of basic supplies, including food, fuel and medicines, has driven up prices of available supplies," Spindler said. Despite security risks, UNHCR and its partners have delivered emergency non-food aid to some of the neediest civilians. "UNHCR is continuing to scale-up its presence in Donetsk city and is currently looking at the feasibility of an increased presence in Luhansk," Spindler said.