Japan has cleared up just five percent of the rubble left by last year's earthquake and tsunami, the government said Tuesday, amid fears it has been contaminated following the Fukushima nuclear accident.

The twin disasters, which devastated the northeastern coastal communities last year, left almost 23 million tonnes of rubble in the hardest-hit prefectures of Iwate, Miyagi and Fukushima alone.

Getting rid of the giant piles of debris is essential for communities in the disaster zone to be rebuilt.

But despite calls for national solidarity contamination fears have led local authorities around the country to refuse to allow the debris to be disposed of near them.

Currently only Tokyo and Yamagata prefecture have accepted some of the burden, while other regional governments have not been able to offer help in the face of strong opposition from residents.

The government aims to clear up all the disaster rubble by March 2014, but Environment Minister Goshi Hosono said Tuesday it would be "extremely difficult" to achieve this if the pace of processing continues at such a slow pace.