TOKYO -- All 17 ministers in the administration of Japanese Prime Minister Junichiro Koizumi resigned on Monday ahead of the launch of his new cabinet, officials said.

As a formality, the ministers presented their resignation letters to Koizumi during a special cabinet meeting Monday morning, officials said.

Koizumi, who easily prevailed as president of his party in a leadership election on Saturday, is expected to announce the lineup of new cabinet members within a few hours with the focus on key posts central to his policies on structural reforms, the economy and North Korea. The fate of Heizo Takenaka, the unelected minister most closely associated with Koizumi's reforms because of his crackdown on the troubled banking system, is being closely watched.

A key Koizumi aide hinted Sunday that Takenaka may keep either of his two posts -- minister for financial affairs or minister for economic and fiscal policy.

Reports have suggested former Bank of Japan bureaucrat and Harvard-educated ruling Liberal Democratic Party (LDP) lawmaker Yasuhisa Shiozaki, 52, would replace Takenaka as the chief financial system regulator, AFP reported.

Shiozaki, twice elected, has argued for the same kind of tough stance on banks as Takenaka, with tough asset assessments followed by public injections of funds and changes in management. If appointed financial affairs minister, Shiozaki would head the Financial Services Agency, which regulates the banking system.

The replacement for Masajuro Shiokawa, the 81-year-old finance minister who has said he would quit for health reasons, has also been under scrutiny.

Some tipped Taro Aso, the 63-year-old former LDP policy chief and economic and fiscal policy minister, for the post. Aso has argued economic growth should come before reforms, while also pushing for land and equity tax reform.

Aso, who served in the short-lived pre-Koizumi cabinet of Yoshiro Mori, had been criticized however for not achieving much during his tenure as head of the economic planning agency under former premier Ryutaro Hashimoto.

Koji Omi, 70, former planning agency chief under Hashimoto's second cabinet, was also seen as a candidate for finance minister.

Former foreign minister Masahiko Komura, 54, who came last in the four-way LDP leadership election won by Koizumi, was seen regaining the foreign minister's job.

Komura was the prime minister's special representative and was sent to Iraq in August to observe the conditions and meet U.S. authorities.

Naoki Inose, a 56-year-old author and member of the premier's highway privatization committee who is not an elected lawmaker, is seen as a candidate for transport minister.

Koizumi has said he would retain right-hand man Yasuo Fukuda, 67, as chief cabinet secretary, the government's top spokesman. Trade minister Takeo Hiranuma appeared to rule himself out of a job, by indicating he would not vote for Koizumi.