Lebanese President Michel Aoun said on Saturday that international aid pledged following a massive explosion in Beirut last week that killed 178 people and made 300,000 homeless should go where it is needed. In an interview with French news channel BFM TV, Aoun said all hypotheses remained open in the investigation into the blast at the port of Beirut that wrecked huge swathes of the capital. "I have asked that aid sent by foreign countries be given exactly where it is needed," he said, adding that he had not considered resigning, after the government quit earlier in the week. The United Nations has launched a $565 million aid appeal, whose priorities include stabilizing the grain supply after the explosion destroyed a huge grain silo at the port. Six hospitals and more than 20 clinics were damaged and more than 120 schools destroyed, the UN says. "We would like to be able to rebuild the three hospitals that were completely destroyed," UN humanitarian coordinator Najat Rochdi said earlier. The United States called for a transparent and credible investigation into the disaster. The Aug. 4 blast, which authorities say was caused by more than 2,000 ton of ammonium nitrate that had been unsafely stored at the port for years. "We can never go back to an era in which anything goes at the port or the borders of Lebanon that had to contribute to this situation," said David Hale, US Undersecretary of State for Political Affairs, after visiting the port. He said FBI agents would arrive this weekend, at the invitation of Lebanon, to help investigate what led to the explosion.