TOKYO — Japan will scrap a plan to increase nuclear power from 30 percent to half of the nation’s energy source and will promote renewable energy as a result of its ongoing nuclear crisis, the prime minister said Tuesday.

Naoto Kan told a news conference that Japan needs to “start from scratch” on its long-term energy policy after the Fukushima Dai-ichi nuclear power plant was heavily damaged by the March 11 earthquake and tsunami and has been leaking radiation ever since.

Kan said nuclear and fossil fuel used to be the pillars of Japanese energy policy but now it will add two more — renewable energy such as solar, wind and biomass, and a conservationist-oriented society as a fourth pillar.

“We will thoroughly ensure safety for nuclear power generation and make efforts to further promote renewable energy,” an area where Japan has lagged behind Europe and the U.S., he said.

Kan also said he would take a pay cut beginning in June until the Fukushima nuclear crisis is resolved to take responsibility as part of the government that has promoted nuclear energy. He didn’t specify how much of a pay cut he would take.

The operator of the stricken power plant, Tokyo Electric Power Co., has been struggling for nearly two months to restore critical cooling systems that were knocked out by the disaster. Some 80,000 people living within a 12-mile (20-kilometer) radius of the plant were evacuated from their homes on March 12, with many living in gymnasiums.

On Tuesday, about 100 evacuees were allowed into that exclusion zone briefly to gather belongings from their homes.

The excursion marked the first time the government has felt confident enough in the safety of the area to sanction even short trips there. Residents have been pushing hard for weeks for permission to check up on their homes.

The evacuees — just a fraction of the tens of thousands forced to flee when the plant started leaking radiation after the quake and tsunami — boarded chartered government buses for the two-hour visit.

They were provided with protective suits, goggles and face masks to wear while in the zone, and were issued plastic bags to put their belongings in. They were also given dosimeters to monitor radiation levels and walkie-talkies.

Government and TEPCO officials have said that it could be six to nine months before the plant is brought to a cold shutdown and residents might return to resume their lives. But they admit even that is a best-case scenario.

Kan said Japan will have to compile Japan’s new energy policy in a report for submission to IAEA ministerial conference in June. He didn’t give any numerical estimates for each source of energy to be mentioned in a new policy.

He promised a thorough investitgation of the accident and promised to share data from the accident with the international community.

Associated Press writer Eric Talmadge contributed to this report.