The head of the UN's nuclear watchdog said the agency is considering opening a branch office in Fukushima to monitor efforts to contain the world's worst atomic accident since Chernobyl, a report said.

The Japanese government has struggled with public trust over nuclear energy since the March 11 disaster and had asked the International Atomic Energy Agency (IAEA) to open an office, which will help share information on the crisis at the Fukushima Daiichi plant.

"We have told the Japanese government that the IAEA stands ready to cooperate," the agency's chief Yukiya Amano told Kyodo News on Saturday in the Swiss resort of Davos, where the World Economic Forum is being held.

"While the headquarters in Vienna will continue to deal with issues related to the decontamination and disposal of spent nuclear fuels, we'll be able to have close contact."

A press officer for the IAEA in Tokyo, who is accompanying an ongoing mission to Japan, said no firm decision had yet been made, but that the government's request was being given "careful consideration".

The Nikkei newspaper independently reported from Davos the IAEA chief had stated his intention to open a local office.

Fuji News Network also reported Amano, who is Japanese, was intending the office would be opened, saying it could "strengthen communications with people on the spot."

Tokyo wants an international seal of approval for the energy-hungry country's nuclear industry to bolster its faltering efforts at reassuring the public it is safe to resume atomic operations.

The vast majority of Japan's 54 commercial nuclear reactors are offline because popular opposition has prevented them being restarted in the wake of the Fukushima nuclear crisis.

The disaster, triggered by the March 11 earthquake and tsunami, contaminated the environment and forced tens of thousands of residents around the Fukushima nuclear site, in northeast Japan, to evacuate their homes.

Many still do not know if or when they will be able to return.

Foreign Minister Koichiro Gemba, whose parliamentary constituency is in Fukushima, told residents last week that he was pushing for an office after requests from local leaders.