Japan is to invest hundreds of millions of dollars to stem leaks of radioactive water from the Fukushima nuclear plant.
Government spokesman Yoshihide Suga said an estimated 47bn yen ($473m, £304m) would be allocated to the project.
The leaks were getting worse and the government “felt it was essential to become involved to the greatest extent possible”, Mr Suga said.
The plant was crippled by the 2011 earthquake and tsunami.
The disaster knocked out cooling systems to the reactors, three of which melted down.
Water is now being pumped in to cool the reactors, but storing the resultant large quantities of radioactive water has proved a challenge for plant operator Tokyo Electric Power Company (Tepco).
Under the government plan, a wall of frozen earth will be created around the reactors using pipes filled with refrigerant to prevent groundwater coming into contact with contaminated water being used to cool fuel rods.
Water treatment systems will also be upgraded to tackle the build-up of contaminated water, officials said.
The damage to the plant has necessitated the constant pumping of water to cool the reactors – a process which creates an extra 400 tonnes of contaminated water every day.
It was revealed last month that some of that water was leaking from storage tanks at the site.