Tokyo: Japanese Prime Minister Naoto Kan on Friday announced his resignation as leader of the Democratic Party of Japan, news agency reported and who came to power in June last year had seen his approval ratings fall to below 20 percent due in part to widespread dissatisfaction with how he was handling the aftermath of the March 11 quake that crippled the Fukushima nuclear power plant.

Whoever the party selects as its new leader Monday is almost certain to become Japan's next prime minister - its sixth since 2006.

Potential successors include former Foreign Minister Seiji Maehara, Finance Minister Yoshihiko Noda and Trade Minister Banri Kaieda.

In June, Kan pledged to resign after lawmakers had passed three pieces of legislation, including one related to post-earthquake reconstruction.

The final two bills went through Parliament earlier on Friday. Kan believes the two bills - a deficit-financing bond bill and a new energy promotion bill - will push forward his reconstruction policies.