Mikio Shimoji, secretary general of Kokumin Shinto (People's New Party), said Thursday that the party has decided to dismiss President Shizuka Kamei and policy chief Akiko Kamei over their stances on the consumption tax hike.

The two have asserted that Kokumin Shinto, the junior coalition partner of the ruling Democratic Party of Japan, should leave the coalition because of their opposition to Prime Minister Yoshihiko Noda's tax hike legislation, but the majority of its members are reluctant to do so.

Shimoji said that Financial Services Minister Shozaburo Jimi, the party's sole representative in the Cabinet, will take over as president and said the party will maintain its partnership with the DPJ, underscoring the increasing isolation that its outspoken veteran leader is facing.

House of Councilors member Takashi Morita of Kokumin Shinto told reporters the party decided to dismiss Kamei because he "reversed the party's decision to maintain the coalition on his own authority and took the political party into his own hands."

Last Friday, the Cabinet approved a controversial bill to double the 5 percent consumption tax rate in two stages, to 8 percent in April 2014 and to 10 percent in October 2015, to cover swelling social security costs.

The proposal prompted Kamei to tell Noda that the small party would leave the coalition, but the move appears to have shattered the small party.

But DPJ Acting Secretary General Shinji Tarutoko told reporters late Thursday that the coalition will "stay together" and said Kamei's dismissal was effected "through formal procedures."