The opposition parties, not satisfied with Finance Minister Shoichi Nakagawa's abrupt resignation Tuesday and scenting the possibility of a bigger scalp, demanded Wednesday that Prime Minister Taro Aso apologize for the political turmoil.

The Democratic Party of Japan, Japanese Communist Party, Social Democratic Party and Kokumin Shinto (People's New Party) announced they would not resume deliberations of the budget and related bills in the Diet until Aso apologizes.

"Aso is responsible for triggering deep public distrust and insecurity in politics and causing a delay in Diet proceedings," said DPJ Diet affairs chief Kenji Yamaoka. "Aso must first apologize for and explain (the resignation) to the public at a Diet" committee.