Updated

Japan's prime minister made a final plea for unity on a tax hike vote Tuesday that has divided his ruling party and could weaken his hold on power.

Prime Minister Yoshihiko Noda told Parliament the sales tax hike and other measures are needed to bolster Japan's economy and reduce public debt.

"This reform is not just for our generation. But for our future," Noda said, adding that it would demonstrate Japan's resolve to decisively handle its economic problems.

The vote is to be held later Tuesday. It has support of opposition parties and is expected to pass, but members of a rival bloc in the ruling party have suggested they may quit the party in protest of the tax plan.

Voters appear to be mixed on the plan to double the nation's sales tax to 10 percent over the next three years. Last year's tsunami disaster has made many Japanese more willing to make sacrifices to help their country recover, though they are concerned over how the higher taxes will affect their personal finances.

Even so, the economic debate has been largely overshadowed by the political in-fighting.

Leading the revolt is influential party elder Ichiro Ozawa, who has often criticized Noda and controls a powerful bloc of lawmakers in the ruling party. Ozawa has suggested he may leave the party and take as many lawmakers as he can with him to form a new party.

A party split could make it harder for Noda to work with Parliament to achieve his other policy goals. If 54 or more lawmakers join Ozawa, Noda's party would lose its majority in the lower house of Parliament altogether and could be forced to call general elections.

Noda has only been in office since September.

He has made the tax hike the centerpiece of his efforts to strengthen Japan's economy, which was hit hard by last year's devastating earthquake and tsunami but has been sputtering for years under one of the largest public debt burdens in the developed world.