The parliament opened a 24-day extraordinary session on Thursday as Prime Minister Shigeru Ishiba seeks to enact political reform legislation and a supplementary budget.

He is expected to face intensified pressure from opposition parties after his ruling coalition lost its majority in the powerful House of Representatives in an election last month.

Ishiba, who took office in October, will deliver a policy speech in both parliamentary chambers on Friday, followed by question-and-answer sessions from Monday through Wednesday.

Budget committee discussions, which will be attended by Ishiba and all of his cabinet ministers, are scheduled to take place at the Lower House on Dec. 5 and at the House of Councilors, or the Upper House, on Dec. 6.

Jun Azumi of the Constitutional Democratic Party of Japan will chair the Lower House Budget Committee, becoming the first opposition lawmaker to assume the important post in three decades.

The ruling camp and some opposition parties, including the CDP, have broadly agreed to scrap the so-called policy activity funds provided by political parties to member lawmakers, as part of political reform.

Meanwhile, the Liberal Democratic Party, the dominant partner in the ruling coalition, is cautious about an opposition demand for banning political donations by companies and organizations.

Deliberations on the supplementary budget, designed to finance the government's ¥39 trillion economic package, will start on Dec. 9.

The economic package, adopted last week, includes plans to raise the minimum annual taxable income, a measure proposed by the opposition Democratic Party for the People.

"We will discuss (the threshold hike) as part of the tax system reform for fiscal 2025 and raise it," Ishiba will tell both chambers of parliament Friday.

He will also say that the government will "consider and reach a conclusion on a general review of automobile-related taxes," including a possible cut in gasoline tax through the scrapping of a provisional additional levy.

He will seek understanding from those worried about an expected fall in tax revenues as a result of the tax reviews, vowing, "We will reach a conclusion on a way to settle the issue."

On regional revitalization, one of his signature policies, Ishiba will declare that his government will double related grants to local governments on an initial-budget basis.