Japan's largest opposition party submitted a no-confidence motion against the top government spokesman on Monday over accusations he failed to report millions of yen received as part of fundraising efforts for his ruling party faction.

The Constitutional Democratic Party of Japan brought the motion against Chief Cabinet Secretary Hirokazu Matsuno. Jun Azumi, Diet affairs chief of the opposition party, told reporters that keeping Matsuno, a Liberal Democratic Party member, in his post "would harm the national interest," given he has neglected to swiftly respond to the allegations.

Japanese Chief Cabinet Secretary Hirokazu Matsuno (C) is surrounded by reporters upon arriving at the premier's office in Tokyo on Dec. 11, 2023, amid a series of political fundraising scandals involving Matsuno and other Liberal Democratic Party lawmakers belonging to the party faction previously led by former Prime Minister Shinzo Abe. (Kyodo) ==Kyodo

Matsuno said at a news conference that the fate depends on the upcoming vote, and in the meantime, all he can do is continue "fulfilling my responsibilities." The no-confidence motion is expected to be voted down in the House of Representatives, which the LDP dominates.

The move comes as Prime Minister Fumio Kishida, who heads the LDP, has already decided to fire Matsuno over his alleged failure to declare more than 10 million yen ($69,000) in income over the past five years, a source close to the matter said.

Allegations have been leveled against several key Cabinet and LDP figures from the largest faction, formerly headed by slain Prime Minister Shinzo Abe, including economy minister Yasutoshi Nishimura and LDP policy chief Koichi Hagiuda.

Hagiuda told reporters he is deciding whether to step down from the post.

Jun Azumi, Diet affairs chief of the Constitutional Democratic Party of Japan, speaks to reporters in the parliament building in Tokyo on Dec. 11, 2023. (Kyodo) 

Among other Abe faction lawmakers, Seiko Hashimoto, a House of Councillors member who served as president of the now-defunct Tokyo Olympic and Paralympic organizing committee, is also suspected of having failed to report income raised through parties, investigative sources said.

The scandal emerged following a criminal complaint alleging five LDP factions, including Kishida's group, underreported revenue from political fundraising parties.

Prosecutors are looking into a possible violation of the political funds control law after hundreds of millions of yen allegedly collected by Abe's faction through fundraising parties went unreported in political funding statements from 2018 to 2022.

LDP factions have traditionally set lawmakers quotas for sales of party tickets, usually priced at 20,000 yen. If they surpass their targets, the extra funds are returned to them as a type of commission.

In the LDP's biggest faction, which Abe headed until his assassination during an election campaign speech in July 2022, the extra funds had neither been reported as expenditure nor as payments to lawmakers, with critics saying it amounts to a form of tax evasion.

Kishida is considering replacing all four ministers, including Matsuno, five senior vice ministers and six parliamentary vice ministers from Abe's faction while looking for the best time to change the composition of his Cabinet after the Diet session ends on Wednesday, the political source said.

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