Japan's upper house is preparing to hold hearings on a political funds scandal that has rattled the ruling Liberal Democratic Party, the LDP secretary general in the chamber said Sunday.

The House of Councillors "will arrange a schedule so it does not hamper deliberations on a fiscal 2024 draft budget," Masaji Matsuyama said on a TV program, after the lower house's political ethics committee held sessions on the matter last week, one of which was attended by Prime Minister Fumio Kishida.

But Matsuyama declined to say who would appear at the hearings of the panel responsible for examining the conduct of lawmakers facing allegations of wrongdoing, citing the need to confirm their intentions.

Japanese Prime Minister Fumio Kishida speaks on Feb. 29, 2024, at a session of the House of Representatives political ethics deliberative council in Tokyo, held for the first time since July 2009 to examine a political funds scandal involving his Liberal Democratic Party. (Kyodo)

The opposition camp has called for the 32 upper house lawmakers allegedly involved in the scandal to appear, mostly members of two LDP factions, including Hiroshige Seko, former LDP secretary general in the upper house.

Around 580 million yen ($3.9 million) in total was received by 82 lawmakers belonging to the two factions, including the largest one formerly led by the late Prime Minister Shinzo Abe, over a five-year period through 2022.

The hearings of the deliberative council on political ethics in the upper house should be televised, as were the House of Representatives political ethics committee sessions, if the ruling and opposition parties agree, Matsuyama said.

The LDP, which has been in power for most of the period since 1955, has come under intense scrutiny amid allegations that some of its factions neglected to report portions of their income from fundraising parties and created slush funds for years.

Kishida, whose appearance before the parliamentary ethics panel on Thursday was the first by an incumbent prime minister, apologized for "inviting suspicion and mistrust" in politics among the public and promised to promote reforms to safeguard compliance in the ruling party.

But the opposition bloc criticized Kishida's appearance before the committee, saying he failed to contribute to uncovering further details of the scandal and only reiterated what he had stated in previous Diet sessions.

Kishida's government is aiming to secure swift passage of a draft budget for the next fiscal year starting April.

The lower house passed the draft budget Saturday after Diet deliberations stalled amid a stalemate over the political ethics committee hearings.

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