There are clear improvements in the situation at the Japanese earthquake-hit Fukushima Daiichi nuclear power plant, the head of the United Nations nuclear watchdog said Monday, and the agency now feels assured the crisis will be solved.

"The accident isn't over," International Atomic Energy Agency Director General Yukiya Amano said at a press conference here. "I would like to underline that the situation at the Fukushima Daiichi plant remains very serious, but we have seen signs of improvement."

Amano highlighted the restoration of power supplies to the plant's six reactors, and of full functionality of the cooling systems at reactor units five and six, which he said "are no longer of immediate concern."

Amano said he "has no doubt that this crisis will be effectively overcome," adding the crisis response of both
Japan and the IAEA calls for an extensive post-crisis evaluation.

"We are doing everything that we can in cooperation with Japan to provide information, but I do understand that the public feels it isn't as extensive as possible, not as fast as possible, and this is also something I would like to see improved," Amano said, talking to the press after an extra-ordinary meeting of IAEA's 35 member nations strong board of governors.

"An extensive process of evaluation will be needed after the accident is over. There will be a stock-taking process," Amano said, conceding there has been room for improvement in the crisis response of both the IAEA and
Japan .