Relief organizations in the Gaza Strip warned of an impending humanitarian crisis Tuesday, with basic supplies dwindling as a result of border closures and military operations. Closed road links and damage to the infrastructure have led to major shortages of basic supplies such as food, water and medicine, United Nations and other nongovernmental organizations said. Electrical outages have become common since the IAF bombed Gaza's main power plant on June 28. Hospitals, water utilities and sewage treatment plants are now dependent on generators, for which spare parts are not readily available. This has created a high demand for fuel, according to the UN's Office of Coordination of Humanitarian Affairs. The power outages mean basic foodstuffs often can't be processed and perishables can't be refrigerated. "We are on our way to a crisis," said Karen Abu-Zayd, commissioner-general of the United Nations Reliefs and Works Agency. "The instability of supplies, the fear and dread of people living in this situation are all points that we define a crisis by," she said. The IDF allowed 14 trucks carrying humanitarian supplies to pass through the Erez crossing into northern Gaza on Tuesday, military officials said. They said trucks carrying sugar and other food, chlorine and medical supplies were allowed through the crossing. On Monday, 250,000 liters of diesel fuel, 50,000 liters of gasoline, and 75 tons of natural gas passed through the southern Nahal Oz crossing. Relief officials and foreign ambassadors met Tuesday with Foreign Ministry representatives to discuss the situation. Ministry officials explained the steps Israel was taking to move aid into Gaza. One official said Israel appeared to be doing "quite a lot." "Israel will do what we can to facilitate the flow of humanitarian support for Gaza. We will do what we can to work together with the international community... to help them do what they have to do," said Foreign Ministry spokesman Mark Regev. The Foreign Ministry had set up a 24-hour hotline to work with humanitarian groups, he said. The supplies went through as six Israeli human rights groups petitioned the High Court of Justice to order an uninterrupted flow of fuel, food, medicine and other items into the Strip. "Without a steady supply of fuel and parts, hospitals cannot perform life-saving surgery, and treatment plants cannot pump and treat sewage in Gaza," the groups wrote. The petition was lodged by The Association for Civil Rights in Israel; Physicians for Human Rights-Israel; Hamoked: Center for Defense of the Individual; B'tselem; The Public Committee Against Torture in Israel; and Gisha - Center for the Legal Protection of Freedom of Movement. According to the petitioners, 60,000 tons of raw sewage is being dumped in the sea daily as treatment plants struggle to cope with power shortages. Also, underground water pipes have been damaged by armored IDF vehicles passing over them, according to a UN report. Also Tuesday, the European Commission said it has started delivering $765,000 in monthly aid to hospitals in the Gaza Strip through an internationally backed mechanism that bypassed the Hamas-led Palestinian Authority government. EU spokeswoman Emma Udwin said it was the first time the union was using the mechanism, set up after Hamas took control of the PA government and the EU froze direct aid. The funds are to be used to purchase fuel for generators at Gaza hospitals, Udwin said. About 85 percent of Gazans are dependent on food handouts, said Kirstie Campbell, a spokeswoman for the UN's World Food Program. The recent violence had made a bad situation worse, and many families were eating only one meal a day, she said. We are very concerned that they are eating such a restricted diet, she said. The food shortage, combined with problems with water and sewage treatment, would increase susceptibility to disease, she said. Campbell said the World Food Program had moved food supplies through the Erez crossing over the past two days, including truckloads of flour and canned meat. "It's not a crisis, but it's very close," said Elizabeth Sime, country director for humanitarian aid provider CARE. Sime said she assumed that Israel would allow enough supplies in to avert a "full-blown" crisis. "The danger is that the most vulnerable members of the community - civilians, women and children - are the ones who suffer most," Sime said. Mothers in poor households were giving children watered-down milk and thickening it with starch, she said, and the situation could lead to chronic malnutrition. Sime said her organization was focusing on efforts to bring in 200,000 liters of fuel. "The NGO community and public institutions can't meet all the humanitarian needs," she said, adding that most of the population was dependent on services that would normally be provided through government institutions, institutions that no longer had the funds. "I find that really distressing," she said. According to the UN, 80% of Gazans live under the poverty line, and 40% are unemployed. Also, the 43% of the population who rely on PA salaries have not been paid for four months. AP contributed to this report.