Parliamentary hearings in Japan to probe a political funds scandal, which has rattled the ruling Liberal Democratic Party, are set to be held for two days from Wednesday, lawmakers said, with five key LDP lawmakers agreeing to participate.

The ruling and opposition camps will formally decide on Monday the format of the political ethics committee session meetings, such as whether they should be open to non-panel member lawmakers and the media, the lawmakers said.

The LDP, led by Prime Minister Fumio Kishida, has come under intense scrutiny amid allegations that three factions, including the one he headed until December, neglected to report portions of their incomes from fundraising parties and created slush funds.

Directors of Japan's ruling and opposition parties attend a House of Representatives budget committee meeting in Tokyo on Feb. 22, 2024. (Kyodo)

Earlier this week, the LDP had announced the attendance of two senior lawmakers -- Ryu Shionoya, the de facto leader of the largest faction formerly led by the late Prime Minister Shinzo Abe, and Ryota Takeda, a senior member of another intraparty group.

But the proposal sparked a backlash from the opposition bloc, which demanded the attendance of more LDP lawmakers. Later, the ruling party said three additional senior members of its biggest faction will attend the House of Representatives council session.

The three are former trade minister Yasutoshi Nishimura, former Chief Cabinet Secretary Hirokazu Matsuno and former LDP Diet affairs chief Tsuyoshi Takagi, all of whom have previously served as secretary general of the Abe faction.

After the latest political funds scandal came to light late last year, the Abe faction decided to disband, and key members within the group resigned from their party or government posts.

While hearings of the ethics panel are, in principle, closed, they are made public when attendees agree. The LDP said its five attending lawmakers have opted for closed-session meetings scheduled to last for an hour each, triggering criticism from opposition parties.

The deliberative council on political ethics, last held in July 2009, is responsible for examining the political and moral conduct of lawmakers who face allegations of wrongdoing.

The council can admonish them, such as by recommending they step down from their roles in the Diet or refrain from attending parliamentary sessions for a period, although no such measures have ever been taken.

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