Japan said Thursday its crisis-hit nuclear plant must be scrapped, but currently had no plans to evacuate more people, despite calls for a larger exclusion zone around the crippled facility.
Grappling with the aftermath of a massive earthquake and tsunami, its biggest post-war disaster, Japan's government hosted French President Nicolas Sarkozy, who called for clear international standards on nuclear safety.
Japan's Prime Minister Naoto Kan said, in talks with the Japanese Communist Party leader, that the facility at the centre of the worst atomic accident since Chernobyl in 1986 must be decommissioned, Kyodo News reported.
Officials have previously hinted the plant would be retired once the situation there is stabilised, given the severe damage it has sustained including likely partial meltdowns and a series of hydrogen blasts.
Iodine-131 in the Pacific Ocean near the plant has risen to a new high of 4,385 times the legal level, the plant's operator Tokyo Electric Power Co. (Tepco) said.
However, there were no plans to widen a 20-kilometre (12-mile) exclusion zone around the Fukushima plant despite the UN atomic watchdog saying radiation at Iitate village 40 kilometres away had reached evacuation levels.
"At the moment, we do not have the understanding that it is necessary to evacuate residents there. We think the residents can stay calm," said Yoshihiro Sugiyama, an official at the nuclear safety agency.
Japan's top government spokesman Yukio Edano also said further evacuations were not imminent, although he did not rule out that this could change.
"We will continue monitoring the level of radiation with heightened vigilance and we intend to take action if necessary," he told reporters.
The comments came after the IAEA added its voice to that of Greenpeace, which has warned for several days that residents, especially children and pregnant women, should leave Iitate village.
The IAEA's head of nuclear safety and security, Denis Flory, told reporters in Vienna that radiation levels there had exceeded the criteria for triggering evacuations.
He said the IAEA - which has no mandate to order nations to act - had advised Japan to "carefully assess the situation, and they have indicated that it is already under assessment."
The reading in Iitate was two megabecquerels per square metre -- a "ratio about two times higher than levels" at which the IAEA recommends evacuations, said the head of its Incident and Emergency Centre, Elena Buglova.
Authorities later said they would Friday lift restrictions issued earlier on drinking tap water in the village, public broadcaster NHK reported.
French President Nicolas Sarkozy arrived in Tokyo on Thursday in a show of solidarity with the disaster-hit nation, and urged nuclear authorities in the Group of 20 to establish an international safety standard.
"We call on the independent authorities of G20 members to meet, if possible in Paris, to define an international nuclear safety standard" for power plants, he said in a speech earlier in the day at the French Embassy in Tokyo.
"It is absolutely abnormal that these international safety standards do not exist," he said, suggesting the Paris meeting could take place as early as May.
French nuclear group Areva is assisting Tepco, which runs the Fukushima Daiichi plant, and the Japanese utility has asked it to provide more help, said Areva Japan president Remy Autebert.
"We'll need a bit of time, but our actions will probably increase in response to their requests," he told AFP.
About 150 Marines of the US Chemical Biological Incident Response Force were due to arrive Friday, although there were no plans for them to take part in the emergency work to stabilise Fukushima, US defence officials told AFP.
They will not penetrate a 50-mile (80-kilometre) radius around the stricken plant, a zone which the US has advised its citizens to avoid, officials said.
At the plant itself, workers pushed on with the high-stakes battle to stabilise reactors, into which water has been poured to submerge and cool fuel rods that are assumed to have partially melted down.
They are also struggling to safely dispose of thousands of tons of highly contaminated run-off water.
Japan has considered a range of high-tech options -- including covering the explosion-charred reactor buildings with fabric, and bringing in robots to clear irradiated rubble.
A US military barge carrying more fresh water to be pumped into the reactors docked off the plant Thursday, the nuclear safety agency said.
Workers also plan to spray an industrial resin at the plant to trap settled radioactive particles, although plans to start Thursday were delayed because of weather conditions.