The government and the Liberal Democratic Party-New Komeito ruling bloc on Wednesday officially authorized a midterm tax reform program to increase the 5 percent consumption tax in fiscal 2011 if the economy improves.

Prime Minister Taro Aso held a news conference to stress the need to bump up the sales levy to cover snowballing social security costs, but he did not specify how high the tax would be hiked.

"This tax increase is to secure stable pension, medical treatment and nursing systems," Aso said. "It is aimed so we don't leave (debts) for our children and grandchildren to pay."