By Michael Shields and Sylvia Westall
VIENNA (Reuters) - The U.N. atomic energy chief called a Vienna summit to tackle mounting concerns about nuclear safety, saying on Monday the international community needed a coordinated response in the wake of Japan's crisis.
Japan is struggling to avert a severe meltdown at its Fukushima Daiichi nuclear power plant and officials said highly radioactive water had been leaking from the site hit by an earthquake and tsunami on March 11.
The disaster has prompted a rethink of nuclear power around the world, just as the technology was starting to regain momentum as a tool to fight global warming.
The International Atomic Energy Agency (IAEA), which promotes peaceful uses of nuclear energy, would host the meeting, possibly in June, Director-General Yukiya Amano said.
He said ministers from 151 IAEA member states should attend.
"(The) political level is needed, this is a very important issue, this is not only for experts or technical people," he told a news conference.
Amano said the Vienna conference would discuss the initial assessment of the Japanese accident and look at where things went wrong. It would also focus on boosting atomic safety and seek ways to improve nuclear crisis-management.
The IAEA has been criticised in the media and privately by diplomats for being too slow to react to the crisis.
The agency has said it can only communicate the data Japan gives it and says it lacks the power to enforce nuclear safety standards, something it may now lobby to change.
Amano described the situation at the site as "very serious."
"The difficult situation has not been overcome and it will take time to stabilise the reactors. Radioactivity in the environment, foodstuffs and water is a matter of concern in the vicinity of the Fukushima plant and beyond," he said.
