The Liberal Democratic Party on Tuesday decided not to review a punishment it imposed on the de facto leader of its largest faction over his role in the political funds scandal, making it likely that the lawmaker will leave the ruling party.

Ryu Shionoya, chairman of the faction formerly led by the late Prime Minister Shinzo Abe, had sought a review of a recommendation that he leave the party -- the harshest of the punishments handed to dozens of LDP members over the creation of hundreds of millions of yen in off-the-book money from fundraising party revenues for years.

The 74-year-old House of Representatives member has expressed his intention to quit the party if his review request was not accepted, and told reporters Tuesday that he has not changed his mind "in principle." He said a final decision will be made after discussing the matter with his supporters, possibly early next week.

Ryu Shionoya, chairman of the faction formerly led by the late Prime Minister Shinzo Abe, speaks to reporters in Tokyo on April 16, 2024. (Kyodo)

If he does not voluntarily resign within 10 days, he will be expelled.

After the LDP decided to discipline 39 members earlier this month, Shionoya reacted angrily to the tough punishment he faced, saying that it was based on "numerous factual errors" and he demanded a "fair judgement based on the facts."

Shionoya believes he is a "scapegoat," as he was not in the loop of the five most influential figures in the Abe faction, such as former trade minister Hiroshige Seko and former LDP policy chief Koichi Hagiuda.

Shionoya ended up heading the faction in August last year after the group struggled to find a successor to Abe who was fatally shot during an election campaign speech in 2022.

Seko, former LDP secretary general in the House of Councillors, was also advised to leave the party -- the second toughest of the eight penalties available to the party following expulsion -- and did so the same day the punishment was imposed.

Finalizing Shionoya's punishment would mark the end of the LDP's disciplinary actions against its members involved in the scandal, which has rocked the party since the issue came to light late last year and left Prime Minister Fumio Kishida, who doubles as LDP president, facing sluggish Cabinet approval ratings.

Hiroshi Moriyama, who heads the LDP's decision-making general council, told Kishida on Tuesday that Shionoya's request had been rejected and he indicated to reporters that public trust in politics will not recover simply because the disciplinary procedures are over, saying that "things are not as easy as that."

Moriyama told a press conference that the punishment complied with party rules and there were no "flaws" in the decision.

The Abe faction is among the groups that have decided to disband in the wake of the scandal.

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