The Diet approved a bill Wednesday that will enable the government to raise income tax for up to 25 years to secure funds for reconstruction work following the March quake and tsunami.

The bill, approved last week by the Lower House, was endorsed by the Upper House, with Prime Minister Yoshihiko Noda's coalition obtaining the cooperation of major opposition parties that dominate the Upper House.

The Diet has already enacted a ¥12 trillion extra budget mainly to cover the additional costs for rebuilding areas in the northeast devastated by the March 11 disasters, which also triggered the crisis at the Fukushima No. 1 nuclear power plant.

Noda wants to use the money from the tax hikes, some of which will start next April, to service special government bonds. He has refused to issue new debt without ensuring that the government has sufficient redemption funds to improve the country's fiscal health, the worst among major developed countries.

The government plans to increase the personal income tax for 25 years starting in January 2013 despite concerns by economists and lawmakers that this would hurt the already fragile consumer confidence.