Updated

Experts say they're skeptical about a plan to build a costly underground frozen wall at Japan's crippled nuclear plant.

The experts and Japanese nuclear regulatory officials said Friday that they weren't convinced the project can resolve the contaminated water problem at the Fukushima Dai-ichi plant, which suffered meltdowns following the 2011 earthquake and tsunami.

The frozen wall is a 32 billion yen ($320 million) government-funded project to surround the plant's four crippled reactors and their turbine buildings with an underground ice wall to block groundwater from flowing into the buildings' basements and mixing with highly radioactive water leaks from the melted cores.

Government officials say a feasibility test has proved successful and they hope to start construction in June, though the project could be delayed because of the experts' concerns.