Japan's ruling Liberal Democratic Party is considering imposing severe punishments on four of its senior members over their involvement in a political funds scandal, with non-endorsement in elections among the possible penalties, sources familiar with the matter said Saturday.

The four members in question are former education minister Ryu Shionoya, former LDP policy chief Hakubun Shimomura, former trade minister Yasutoshi Nishimura -- all House of Representatives members -- and Hiroshige Seko, former LDP secretary general in the House of Councillors.

Japanese Prime Minister Fumio Kishida delivers a speech at the ruling Liberal Democratic Party's congress in Tokyo on March 17, 2024. (Kyodo) ==Kyodo

According to the sources, Prime Minister Fumio Kishida plans to conduct next week additional questioning of the four, who were all senior members of the party's largest faction once led by former premier Shinzo Abe, assassinated in July 2022.

The faction is at the center of a scandal where portions of fundraising party revenue were allegedly handed back to members to create a slush fund.

All four attended a senior-level meeting in April 2022 where Abe, who headed the faction at the time, directed that the practice of transferring the extra funds to its members be halted. They met again in August that year after Abe's death to discuss how to handle the situation.

Although the four each provided explanations at a council on political ethics in both the upper and lower houses of parliament, their testimonies differed, leaving it unclear how the slush fund practice came to be reinstated.

The LDP is considering simultaneously penalizing around 80 of its lawmakers related to the scandal, including the four members, as early as April.

Combined photo shows (clockwise from top L) former education minister Ryu Shionoya, former Liberal Democratic Party policy chief Hakubun Shimomura, Hiroshige Seko, former LDP secretary general in the upper house, and former trade minister Yasutoshi Nishimura. (Kyodo)

Party leaders, including Kishida and Secretary General Toshimitsu Motegi, will make the final decision on who will be subject to punishment and its extent.

Disciplinary action based on party rules comes in eight levels of severity, with non-endorsement in elections the fourth heaviest. Even heavier penalties are suspension of party membership, recommendation for departure, or expulsion.

It is highly likely that junior and mid-level lawmakers with relatively minor discrepancies in their political funding reports will face lighter punishments such as suspension of party positions or warnings.

"As a party, we believe that further efforts are needed to verify the facts. We want to reach a conclusion promptly on the issue of political responsibility and accountability," Motegi told reporters in Wajima, Ishikawa Prefecture, on Saturday.

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