TOKYO Tue Mar 10, 2015 11:18am GMT

Japanese Prime Minister Shinzo Abe on Tuesday vowed to draw up a new-five year plan to speed rebuilding from a massive 2011 tsunami and the world's worst nuclear disaster since Chernobyl that have left thousands still homeless.

Abe spoke ahead of the fourth anniversary of the devastating March 11 earthquake, which set off a massive tsunami that ravaged the Pacific coastline, killing nearly 20,000 and causing explosions and meltdowns at the Fukushima Daiichi nuclear plant.

Much remains to be done, with many towns struggling to provide jobs and permanent housing for thousands of residents, Abe told a news conference, adding that the government would prepare a new five-year reconstruction plan by this summer.

"We in the Abe government will provide all the support needed for the people in the devastated areas, who are working so hard to rebuild their lives and move ahead," Abe said.

"The current intensive five-year reconstruction plan expires next March, but we will draw up another for the next five years by this summer," he added.

He declined to give any details of the budget, apart from saying it would be decided in talks with local governments. It is estimated that the government has paid out as much as $50 billion to the three regions hardest hit by the disaster.

Abe added that the government would continue to spearhead efforts in dealing with contaminated water from the wrecked Fukushima plant, as well as its decommission.

Since the 9.0 magnitude quake, Japan has allocated more than $15 billion to an unprecedented project to lower radiation in towns near the plant, with irradiated trash piling up in 88,000 temporary storage facilities nearby.

Tokyo plans to build a more permanent storage facility in several towns abandoned due to the accident, despite opposition from some residents, a decision Abe alluded to by thanking those in agreement with the plan.

"We in the government will continue to do everything possible to deal with the issue of irradiated water as well as decommissioning the plant," he said.

"It may only be by slow steps, but reconstruction is definitely moving into a new stage."

Abe, along with Emperor Akihito, will attend Wednesday's ceremonies to mark the quake anniversary. Tokyo's subway trains will stop for a minute at 2:46 p.m. (05:46 GMT), the time the quake struck.