Japan's Prime Minister Naoto Kan attends a plenary session at the Lower House in Tokyo August 23, 2011. [Photo/Agencies]

TOKYO - Prime Minister Naoto Kan confirmed on Friday he would resign as ruling party leader, Kyodo news agency said, setting the stage for Japan to pick its sixth premier in five years as it tries to rebuild from a massive earthquake and tsunami, forge a new energy policy after a nuclear crisis and curb huge public debt.

As many as seven ruling Democratic Party of Japan (DPJ) lawmakers are jostling to replace Kan in a DPJ leadership vote set for August 29.

They include former foreign minister Seiji Maehara, a security hawk, and Finance Minister Yoshihiko Noda, a fiscal conservative. The winner will become premier by virtue of the party's majority in parliament's lower house.

Successive governments have struggled to address deep policy problems in the face of a divided parliament and rifts inside the ruling party.

Kan's approval ratings fell below 20 percent due to policy inconsistencies and dissatisfaction with his handling of the radiation crisis at a tsunami-crippled power plant. His defenders say the former civic activist also ran into trouble due to his call to wean Japan from nuclear power - a stance popular with the public but opposed by many senior politicians.