The tsunami of 11 March was the 'direct cause' of the accident at the Fukushima Daiichi nuclear power plant, concluded an official investigation report. It dismissed the idea that earthquake damage was a major factor in the accident.

A new analysis of the accident at Fukushima Daiichi indicates more extensive melting probably occurred at unit 1 than previously thought, although the predicted status of units 2 and 3 remains about the same.

The cost of generating electricity with nuclear power plants could rise by as much as ¥1.60 ($0.02) per kilowatt-hour if the risk of a serious accident is factored in, according to the Japan Atomic Energy Commission. Meanwhile, a French utility group has warned that cutting France's dependency on nuclear energy would be an expensive option.

The origin of xenon in the containment of Fukushima Daiichi 2 is currently considered to be spontaneous fission, a process of radioactive decay not involving any chain reaction.

The possible detection of xenon at Fukushima Daiichi 2 has led to questions over ongoing fission, but detection is uncertain and a translation error may have exacerbated anxiety.

Electricity of Vietnam has signed an agreement with a consortium of Japanese companies to progress the design, construction and operation of the country's second proposed nuclear power plant. Meanwhile, Rosatom will help establish a nuclear energy information centre in Hanoi.

The effort to decontaminate the area around Fukushima Daiichi is gathering pace with the goal of enabling the return of residents evacuated some six months ago.

The operation of a core spray has helped to bring the temperature of Fukushima Daiichi 3 below 100ºC - the benchmark for cold shutdown.

The costs of generating electricity using nuclear power plants in Japan, even taking into account the compensation costs related to the Fukushima Daiichi accident, still remain likely to be less than using fossil fuels, according to a new study.

The temperature of the reactor core of unit 3 of the damaged Fukushima Daiichi plant is expected to drop significantly with the commissioning of a more efficient cooling system, according to Tokyo Electric Power Company (Tepco).

Some stabilisation targets have been met at the Fukushima Daiichi nuclear power plant, but levels of contaminated water in the basements remain Tepco's biggest challenge.

Japanese authorities are to start detailed studies which could lead to a re-assessment of the evacuation measures in Fukushima prefecture.