The government needs to compile an extraordinary budget of more than ¥10 trillion to bolster the economy, a senior ruling party official said Tuesday.

"As uncertainty grows about the economic outlook, (the government) cannot remove the public's anxiety without a large-scale supplementary budget," Toshihiro Nikai, secretary-general of the Liberal Democratic Party, said at a news conference.

Nikai, who holds the LDP's No. 2 post after Prime Minister Shinzo Abe, stressed the importance of strengthening infrastructure-building and reconstruction efforts in the face of increasingly severe natural disasters hitting the country.

The government is crafting the extra budget to assist reconstruction in areas devastated by a series of disasters this year, including deadly Typhoon Hagibis in October.

Finance Minister Taro Aso, however, questioned Nikai's suggestion, telling reporters that he needs to show fiscal sources for the proposed budget.

"Where would ¥10 trillion come from?" asked Aso, who doubles as deputy prime minister.

The scale of Nikai's plan compares with the country's ¥101.46 trillion initial budget for fiscal 2019.

Earlier this month, Abe instructed ministers to draw up an economic package to cushion downside risks at home and abroad, including the impact of the Oct. 1 increase in the consumption tax from 8 percent to 10 percent.

The government plans to earmark necessary funds for the package in the fiscal 2019 supplementary budget and in the fiscal 2020 budget.