TOKYO - Japan's Prime Minister Shinzo Abe will shake up his Cabinet this week, the government's top spokesman said on Tuesday, as public support plummets after a series of scandals.

Abe himself has faced claims he used influence to help a friend in a business deal, an accusation he denies, while the country's defense minister resigned last week following a controversy over military documents.

Abe told ministers he was planning a reshuffle on Thursday to "push ahead with various reforms under a new lineup", Chief Cabinet Secretary Yoshihide Suga said.

Suga said the new Cabinet's top priority would be reviving the economy, adding it would also work to ensure national security.

Staunch nationalist Abe became prime minister for a second time in December 2012 with a vow to rejuvenate the world's third-largest economy.

Public support ratings for Abe's Cabinet have fallen precipitously over the summer, with voters punishing his Liberal Democratic Party in local Tokyo elections a month ago.

Abe had been expected to get rid of Tomomi Inada, a close confidante but deeply unpopular as defense minister, in the widely expected reshuffle.

But she resigned on Friday over a long-brewing scandal involving the handling of military reports, along with the chief of staff of the Ground Self-Defense Force and the top ranking civil servant in the ministry.

Japanese leaders often make Cabinet changes to reboot their fortunes when times get tough, though political analysts are sceptical over whether the upcoming shuffle will drag Abe out of the political doldrums.

Suga declined to comment on who will be in the new Cabinet, though news reports have said Finance Minister Taro Aso, who also serves as deputy prime minister, and some other ministers will stay.

Meanwhile, prosecutors in the western city of Osaka on Monday arrested Yasunori Kagoike, former chief of educational institution Moritomo Gakuen, with ties to Abe's wife Akie, on suspicion of illegally receiving subsidies, media said, reviving a months-old scandal.

Kagoike and his wife Junko were arrested for fraudulently receiving state subsidies to build an elementary school, Kyodo News agency said.

Prosecutors have been investigating the pair over allegations they defrauded the government and received illicit public subsidies to construct an elementary school.

Afp - Xinhua - Reuters