TOKYO, Aug 27: Areas surrounding Japan’s crippled Fukushima nuclear plant could remain uninhabitable for decades due to high radiation, the government warned on Saturday as it struggles to clean up after the world’s worst nuclear disaster since Chernobyl.

Japan faces the daunting task of decontaminating large areas of land around the Fukushima Daiichi nuclear complex, which is still leaking low levels of radiation nearly six months after an earthquake and tsunami triggered a nuclear meltdown.

In a meeting with local officials on Saturday, the government estimated it could take more than 20 years before residents could safely return to areas with current radiation readings of 200 millisieverts per year, and a decade for areas at 100 millisieverts per year.

The estimates, which merely confirm what many experts have been saying for months, are based on the natural decline of radiation over time and do not account for the impact of decontamination steps such as removing affected soil.

A vast area is still uninhabitable around the Chernobyl plant 25 years after that disaster.

The Japanese government unveiled guidelines this week with the aim of halving radiation in problem areas in two years, but for spots with very high readings it could take much longer to reach safe levels.

“I can't deny the possibility that it could be a long time before people can return to and live in regions with high radiation levels,” outgoing Prime Minister Naoto Kan was quoted by domestic media as telling Fukushima Governor Yuhei Sato.

Japan has banned people from entering within 20km of the Fukushima plant, located 240 km northeast of Tokyo. Around 80,000 people have been evacuated since the March 11 quake and tsunami and many are living in shelters or temporary homes.—Reuters