The U.N. atomic agency chief said on Monday that Japan's nuclear situation remained very serious but that he had no doubt the country would "effectively overcome" the crisis. "The crisis has still not been resolved and the situation at the Fukushima Daiichi nuclear power plant remains very serious," Yukiya Amano, director general of the International Atomic Energy Agency (IAEA), told an emergency board meeting. But, "I have no doubt that this crisis will be effectively overcome," he said in a statement made available to journalists.