The head of the UN atomic watchdog agency headed for Japan's crippled Fukushima Daiichi plant on Monday to survey efforts to contain the world's worst nuclear disaster in 25 years.
Yukiya Amano, director general of the International Atomic Energy Agency (IAEA), was to wear a radiation protection suit on his visit to study Japan's progress under its "roadmap" to contain the accident.
"I would like to assess what the IAEA can do to help," the former senior Japanese diplomat told reporters at a train station near the site.
"I would like to hear from the crew on the ground about the hardships they go through and their feelings as they do their work day in and day out," he was quoted as saying by public broadcaster NHK.
The Fukushima plant was battered by the March 11 earthquake and tsunami and suffered meltdowns and explosions in the days that followed.
It still releases radioactive material into the environment and has destroyed the livelihoods of tens of thousands of residents who have been evacuated from a 20-kilometre (12-mile) zone and hotspots beyond.
The IAEA criticised Japan's response in a report in June, especially its failure to implement the agency's convention on dealing with nuclear emergencies.
The convention sets out rules for cooperation between the IAEA and states that may need emergency help with security and communication.
A preliminary version of the document, presented earlier in Tokyo, said Japan had underestimated the hazard posed by tsunamis to nuclear plants, but praised Tokyo's response to the March 11 disaster as "exemplary".
Japan and operator Tokyo Electric Power Company are trying to bring the plant's overheating reactors to stable "cold shutdown" by January.
Japan's embattled Prime Minister Naoto Kan has also announced "stress tests", modeled after a similar programme in Europe, for all of the 54 nuclear plants in Japan, the majority of which are currently offline for checks.
Kan, who has resisted weeks of intense pressure to resign soon, has spoken in favour of a nuclear power phase-out in the quake-prone island nation, where atomic power until recently met about 30% of energy demand.