Japan goverement under pressure to widen evacuation zone

An exclusion zone with a radius of 20km (12 miles) is currently in place but the UN says safe radiation limits have been exceeded 40km away.

Meanwhile, radioactive iodine levels in seawater near the plant reached a new record - 4,385 times the legal limit. It was the highest reading since the quake which wrecked the plant on 11 March.

Japan’s Nuclear and Industral Safety Agency (Nisa) said radiation may be leaking from the damaged plant continuously. The plant's operator, Tokyo Electric Power (Tepco), announced on yesterday that the four stricken reactors would be decommissioned.

A massive tsunami which resulted from the quake is now known to have claimed at least 11,417 lives, with 16,273 people still reported missing by police, three weeks on.

The UN's nuclear watchdog (International Atomic Energy Agency, IAEA) found safe radiation limits had been exceeded at the village of Litate, 40km north-west of the nuclear plant.

"The highest values were found in a relatively small area in the north-west from the Fukushima power plant and the first assessment indicates that one of the IAEA operational criteria for evacuation is exceeded in Iitate village," senior IAEA official Denis Flory said.

Japan's top government spokesman, Chief Cabinet Secretary Yukio Edano, commentesd on the IAEA’s advice to "carefully assess the situation on the basis of this report".

"I don't think that this is something of a nature which immediately requires such action," he told reporters.

"But the fact that the level of radiation is high in the soil is inevitably pointing to the possibility that the accumulation over the long term may affect human health.

"Therefore, we will continue monitoring the level of radiation with heightened vigilance and we intend to take action if necessary."