As the Lower House passed a crucial bill authorizing bond-issuances Thursday, lawmakers in the ruling Democratic Party of Japan accelerated their hunt for a successor to Prime Minister Naoto Kan, with former Diet affairs chief Shinji Tarutoko the latest name floated in the Nagata-cho political center.

Tarutoko hinted the same day he might run in the DPJ's presidential race, which would pick the next prime minister.

"Right now, I am only thinking about doing my best to maintain party unity," Tarutoko said in a meeting with lawmakers from his faction. But "when the political schedule becomes clear, I would like to make a decision."