U.S. Secretary of State Hillary Clinton urged Japan on Sunday to remain active on the world stage and pledged support for Washington's key ally in East Asia as the operator of a stricken nuclear plant finally set out a timeline to shut it down.

Tokyo Electric Power Co. (TEPCO) said it it hopes to bring the reactors at its hobbled Fukushima Daiichi nuclear power plant into a stable state known as cold shutdown within the next nine months, during which the three damaged reactor buildings at the facility will be covered.

"Economically, diplomatically and in so many other ways, Japan is indispensable to global problem-solving," Clinton told a news conference after talks with Japanese Foreign Minister Takeaki Matsumoto. "And the U.S.-Japan alliance is as indispensable as ever to global security and progress."

Clinton also said Japan and the United States had agreed to create a "public-private partnership for reconstruction" under the guidance of Japan's government, and that U.S. firms and organisations would begin discussing how they can support Japan as it comes through the crisis.

Soon after she spoke, TEPCO gave a briefing outlining its plan to bring the plant to cold shutdown.

The plan will be carried out in two stages. Tepco will first cool the reactors and spent fuel pools, with the aim of cutting the amount of leaking radiation. It will also decontaminate water that has become radioactive.

The second stage will see Tepco try for a cold shutdown of the reactors and to cover the reactor buildings with what the AP said may be a type of industrial cloth.

Even if the operator does manage to do that within six to nine months, Japan hinted on Sunday that a full recovery was likely to take longer.

"The first juncture towards safety would be when the fuel rods are fully submerged in water and a cold shut down is achieved," said Banri Kaieda, Japan's economics minister.

"But true safety will not come until the fuel rods are removed from the reactors," Kaieda told a news conference on Sunday.
Kaieda also said he advised TEPCO not to dump contaminated water, no matter how low the radiation level, into the ocean in future.

Kyodo News reported Thursday the radiation level of the groundwater had risen 10 fold in one week at the nuclear power plant. Japan’s nuclear safety agency said on the same day, that the level of contaminated water in its underground trench turned out to be rising again.

IBTimes with Reuters