Japanese prime minister Naoto Kan's administration has announced it is to sack three senior nuclear policy officials amid scandals suggesting Japan's government had grown too cosy with the nuclear power industry.

The move is the latest attempt by Kan and his cabinet to shake off criticism they have not dealt sternly enough with nuclear power operators and to show they can push reforms deemed necessary after Japan's 11 March earthquake and tsunami touched off the world's worst nuclear accident since Chernobyl at the Fukushima plant.

The trade and industry minister, Banri Kaieda, said the shakeup would involve three senior officials: the head of the Energy Agency, the head of the Nuclear Industrial Safety Agency and a vice-minister at the trade and industry ministry.

"We want to refresh and revitalise the ministry," Kaieda said. The three posts are under his supervision.

Japan's post-tsunami handling of the nuclear crisis has been hit recently by scandals over allegations that the government was too friendly with the nuclear industry and tried to secretly manipulate public discussions in favour of nuclear power at a number of seminars held before the crisis began.

The shakeup was seen as an attempt to calm that uproar. But Kan's government continues to face a questions about its response to the crisis and even about how long Kan will be able to remain in office.

The growing disarray in Kan's administration was emphasised recently when his cabinet was unwilling to unify itself behind the PM's call for Japan to completely wean itself off nuclear power. Kan had to later step back and explain the comment was a "personal" opinion.

Kan, who faces a strong challenge from party rivals who want him to quit immediately, has said he will step down as soon as the country is on the recovery track. His top lieutenants have suggested that could be soon, but have refrained from setting a date.

Kaieda, one of the most prominent faces in Kan's cabinet, is also expected to announce his resignation but, again, has refused to say when.

He recently broke down in tears under intense questioning in parliament and said he was willing to quit as soon as the proper time came.