Japan's centre-left ruling party is set to choose a new leader next Monday to replace unpopular incumbent Naoto Kan as party president and therefore as prime minister, officials said.
Kan, Japan's fifth premier in as many years, has been expected for weeks to announce his resignation amid stinging criticism over his response to the March 11 quake and tsunami disaster and the Fukushima nuclear crisis.
Kan, 64, has since the Fukushima accident strongly advocated a nuclear-free future for Japan, a position that has put him at loggerheads with the conservative opposition and some members of his own party.
The August 29 election will be held on the condition that two bills -- one of them to promote renewable energy, which Kan has championed -- pass this week, said Democratic Party of Japan (DPJ) secretary general Katsuya Okada.
Parliament would most likely confirm the new premier on August 30.
Finance Minister Yoshihiko Noda, 54, has been seen as the frontrunner to replace Kan, and Trade Minister Banri Kaieda, former transport minister Sumio Mabuchi and several others have also thrown their hats into the ring.
However, the focus is now on whether former foreign minister Seiji Maehara, the public's favourite according to opinion polls, will join the race. Jiji Press reported Monday that Maehara, 49, was preparing to run.
Whoever wins the premier's job faces urgent challenges -- chiefly to rebuild from Japan's worst post-war disaster while keeping in check a public debt mountain that is already twice the size of the economy.
Almost six months after the quake, tens of thousands of people remain in evacuation centres because of the tsunami and the Fukushima nuclear disaster, which alone forced more than 80,000 people from their homes.
Japan's post-quake economic recovery has been threatened by global financial woes, market turmoil and the strength of the yen, which last week hit a new post-war high against the dollar, hurting Japanese exports.
The DPJ's board members agreed on the date for the party meeting to allow for the timely passage of a third extra budget to finance disaster reconstruction, and for steps to tackle the strong yen, Okada said.
He also said that under the schedule the new prime minister will be able to send a new finance minister to a G7 meeting slated for early September.
The DPJ controls the powerful lower house of the Diet after winning a landslide election two years ago that ended half a century of almost unbroken conservative rule, ensuring that the new DPJ president will become Japan's next premier.
Okada said that official campaigning for the DPJ leadership election will begin Saturday, and that there are plans for a debate among candidates Sunday.
"The reason we chose August 29 as the day to elect a new party leader is that we may be able to hold the premiership vote the next day, in the tight parliament schedule," said Okada.
The current parliamentary session is due to end on August 31.