International Atomic Energy Agency (IAEA) chief Yukiya Amano on Friday urged Japan to provide more information on its "extremely serious" crisis, as the battle to regain control of a failing power plant in northern Japan enters a second week.

During talks with Prime Minister Naoto Kan and Foreign Minister Takeaki Matsumoto, the United Nations' nuclear watchdog chief said that the central government needs to make its information regarding the crisis at the Fukushimi No. 1 power plant, 240 km north of Tokyo, more readily available to the United Nations agency and the broader international community.

"There is the opinion in the international community that more detailed information is needed," Amano was quoted as telling the Japanese leader.

And Kan, for his part, said that Japan will try its utmost to overcome the current crisis and disclose more information to the international community as Amano asked him to do.

Upon his arrival in Tokyo earlier in the day, Amano told reporters: "This is not something that just Japan should deal with, and people of the entire world should cooperate with Japan and the people in the disaster areas."

He also said that a four-member team of nuclear experts will first monitor radiation in Tokyo as early as Friday and conduct further tests in the vicinity of the stricken plant thereafter.

The IAEA chief said his team plans to gather comprehensive data that will be useful for the wider international community as well as Japan's government, as efforts to avert a nuclear crisis were widened by Japan's Self-Defense Force, Tokyo firefighters and workers at Tokyo Electric Co.'s (TEPCO) failing No. 1 power plant.