The president of the Japan Atomic Energy Agency (JAEA), Atsuyuki Suzuki has resigned after the country’s nuclear regulator blocked the restart of the Monju prototype fast breeder reactor.

The Nuclear Regulation Authority (NRA) decided, 15 May, that JAEA would not be permitted to make preparations for the restart of the 280 MW Monju FBR until it could confirm improvements to its inspection and maintenance procedures. The reactor has been offline since August 2010.

The NRA cited JAEA’s failure to regularly check key components. In September, it found that JAEA had failed to check almost 10,000 out of a total 39,000 pieces of equipment at Monju on schedule.

In January, the NRA ordered JAEA to change its maintenance rules and inspection plans. However, in a review that has been carried out since then, the NRA has found that JAEA has failed to formulate and adhere to a strict inspection schedule.

JAEA has been given until 23 May to appeal the decision.

Meanwhile, on 16 May JAEA president, Atsuyuki Suzuki submitted his resignation to the minister of education, culture, sports, science and technology.

JAEA said in a statement that it takes the resignation of the president "seriously" and will devote its "utmost effort" to all of its missions including the activities related to Monju, so as to restore public confidence.

Executive vice president Yonezo Tsujikura will act as head of JAEA until a new president is appointed.