TOKYO -- Prime Minister Junichiro Koizumi's Cabinet resigned en masse Monday, paving the way for the him to name a new lineup in an effort to shore up his economic reform plans.

The 17 Cabinet ministers handed in their resignations during a morning Cabinet meeting at Koizumi's official residence, according to Education Minister Atsuko Toyama. Koizumi was to name his new lineup later in the day, and they would then be formally approved by Emperor Akihito.

The shakeup was the first since Koizumi took office in April 2001. It was expected to be minor, with most if not all of his main ministers retaining their posts, and was seen more as a means for his administration to reaffirm its unity behind his fiscal policies.

Koizumi's popularity has risen dramatically since he traveled to North Korea for an unprecedented summit Sept. 17 with leader Kim Jong Il. According to a poll last Sunday by the Mainichi, a major daily, support for him shot up to 67 percent from 43 percent in a similar poll the previous month.

But he continues to be under intense pressure to pull the economy out of its decade-old slump.

Before announcing his intention to shake up the Cabinet, Koizumi made it clear that he would only consider replacements who would help him push through reforms, rather than caving to party pressures by appointing faction favorites, as is tradition.

Attention was focused on the fate of Financial Services Minister Hakuo Yanagisawa, who has been criticized for shying away from aggressive fiscal measures to deal with Japan's troubled banking sector.

Koizumi was also expected to name to his revised Cabinet Yoshitada Konoike -- an Upper House lawmaker and fellow Liberal Democratic Party member unaffiliated to any faction. He would be second upper house lawmaker, along with Home Affairs Minister Toranosuke Katayama, to serve in the Cabinet.

As an indication of his concern to preserve continuity, Koizumi announced last week he will retain his party's three top leaders -- Taku Yamasaki, Taro Aso and Mitsuo Horiuchi -- whose one-year terms expired Monday.