EXPERTS warned today of serious concerns over a plan to build an underground frozen wall at Japan’s disaster-struck Fukushima nuclear plant.

The 32 billion yen (£190 million) government-funded project to surround the plant’s crippled reactors with an underground ice wall aims to stop groundwater from mixing with highly radioactive water leaks.

But Nuclear Regulation Authority commissioner Toyoshi Fuketa raised fears over the scheme.

“We need to know if a frozen wall is effective and, more importantly, we need to know whether it may cause trouble,” he said.

International experts echoed his concern.

Dale Klein, who heads a supervisory panel monitoring plant operator Tepco, said he was unsure the wall was the best option.

“A decision should be based on current science. You have to strike a balance between science and policy,” Mr Klein said. 

“At the end of the day it may be a good alternative, but I’m just not convinced.”