PM Kan spoke with refugees living in a makeshift camp in the fishing village of Rikuzentakata which was decimated by the tsunamis which struck on March 11 when Japan was rocked by a massive earthquake, leaving 28,000 dead and missing.

“It will be a long battle, but the government will be working hard together with you until the end. I want everyone to do their best,” Kan told one survivor in a school that is now an evacuation shelter.

Despite its tsunami-seawalls, Rikuzentaka was flattened into a wasteland of mud and debris and most of its 23,000 population was killed or injured, many swept away by the waves.

Mr Kan later entered the 20 km (12 mile) evacuation zone on April 2 and visited J-village, a sports facility serving as the headquarters for emergency teams trying to cool the six-reactor Fukushima Daiichi plant.

After three weeks, operators of the crippled nuclear power plant are no closer to regaining control of the damaged reactors, as fuel rods remain overheated and high levels of radiation continue to flow into the sea.

Plant operator Tokyo Electric Power Co (TEPCO), Asia's largest power company, has seen its shares drop 80 percent - US$32 billion in market value - since the disaster.

Japan is facing a damages bill which could top US$300 billion - the world's highest from a natural disaster.

Hundreds of thousands of Japanese remain homeless and sheltering in evacuation centers, as the death toll from the disaster continues to rise.