The government's nuclear disaster task force, headed by then prime minister Naoto Kan and including all of his ministers, has no minutes of the meetings that approved the evacuation of people living near the exploding reactors.

The Nuclear and Industrial Safety Agency, which has served as the secretariat for the task force launched on March 11, said it kept no minutes of the meetings, which also decided on the banning of foodstuffs from the area.

"Yes, it is true," said an agency spokesman, without elaborating.

The confirmation came after public broadcaster NHK said Sunday that the agency failed to record the exchanges and decision-making process in the meetings because officials were too busy.

The Cabinet Office, in charge of keeping all public records, said it has told the agency to study what it can do to create a written record of the decision-making processes.

"In the case of emergencies, it is legally permissible to create documents after the event. We have asked the safety agency to consider what can be done," said a Cabinet Office official.

"We need to know about the decision-making process and how information was processed," he said.

The government has been criticised for having failed to keep minutes of other top-level meetings, held as reactors at the Fukushima Daiichi nuclear plant went into meltdown after their cooling systems were swamped by the March 11 tsunami, sparked by a massive earthquake.

A magnitude-9 earthquake and tsunami l March 11 led to a meltdown at the Fukushima nuclear power plant in Japan. The disaster led to a near-global examination of nuclear power safety.

Only five of Japan's 54 nuclear reactors are currently online but Japan's Nuclear and Industrial Safety Agency says that all of the country's nuclear power plants are scheduled to be halted for servicing by the end of April.

"So far we have been evaluating (the tests) by consulting with domestic experts but we would like to achieve a higher level of safety by also taking into account international expertise," Shinichi Kuroki, deputy director general for nuclear power at NISA said at a news conference.

"Opinions we will receive will be reflected in our future evaluation methods so we would like you to evaluate (our tests) rigorously," he said of the IAEA's visit.

IAEA officials said they expect to achieve improvements in safety protocols for nuclear power plants not just in Japan but worldwide as a result of the Japan visit, said James Lyons, the agency's director of nuclear installations.

On Thursday the IAEA delegation is to visit Kansai Electric Power Co.'s Oi nuclear power plant in Fukui Prefecture, which is currently idled for regular checkups.

Kansai Electric concluded in its stress tests that Oi's No. 3 and No. 4 reactors could withstand an earthquake nearly two times more powerful than the maximum estimated earthquake and a 37-foot high tsunami.

But those scenarios predate the Fukushima disaster, an editorial in Japan's Mainichi newspaper points out.

"Officials should at least provide a set of risk evaluation guidelines based on the cause of the Fukushima disaster that the public can understand," the newspaper said.

The government is also providing conflicting information regarding the life of Japan's nuclear power plants.

Goshi Hosono, state minister in charge of the Fukushima disaster said Jan. 6 that the country's nuclear reactors would in principle be decommissioned after they had been running for more than 40 years. Less than two weeks later, however, the government said that exceptions would allow reactors to operate for 60 years.

The IAEA team's Japan visit is scheduled to conclude Jan. 31.

NISA says that following direction from the IAEA and further checks by the Nuclear Safety Commission of Japan, the decision whether or not to bring the idled reactors back online will be up to Japanese Prime Minister Yoshihiko Noda and other designated ministers.