The Japanese Communist Party would not support Koichi Kato as the nation's leader even if the heavyweight LDP member, who is trying to topple the Cabinet of Prime Minister Yoshiro Mori, revolts from the Liberal Democratic Party, according to JCP leader Tetsuzo Fuwa.

The JCP will not join hands with someone who considers himself a "mainstream" LDP member, Fuwa said in an interview, noting that Kato's political stance would not change just because his party affiliation does.

Fuwa made the remarks in response to the growing likelihood of Kato breaking away from the LDP, in which he leads the second-largest faction.

On Friday, Kato said he will vote in favor of a no-confidence motion against Mori's Cabinet, which the JCP and three other opposition parties are planning to submit to the Lower House on Monday. Kato said he has no intention of leaving the LDP, but party executives have agreed to penalize Kato and those who follow his actions -- most likely throwing them out of the party.

Even if Kato physically breaks away from the LDP, however, "He is, after all, no more than a meager reformer (who cannot break the cocoon) of the LDP (in his mind-set)," Fuwa told The Japan Times, adding that Kato's reformist ideas stem from the fear that the LDP would lose public support unless the party makes changes.

"We are aiming to overthrow the LDP-led government, not to support an LDP reformist," he said.

Fuwa said the moves by Kato, a former LDP secretary general, resemble those of Liberal Party leader Ichiro Ozawa seven years ago, when he defected from the LDP but vowed to inherit the LDP's basic policies.

Four major opposition parties have been united in trying to topple the LDP-led government. The largest, the Democratic Party of Japan, has been sending signals to Kato.

DPJ leader Yukio Hatoyama has repeatedly expressed readiness to cooperate with Kato -- provided he leaves the LDP. Fuwa, however, says it is more important to maintain his own party's stance than maintain harmony with other opposition forces.

Referring to the LDP's internal confusion, as seen in a series of inconsistent public remarks by senior party officials that are immediately denied by other members, he said, "That in itself shows the downfall of the LDP."

The LDP is lacking a "political playwright" who makes decisions and sees to it that decisions are carried out, he said. "So, it's unclear what move the three coalition parties will take once the no-confidence motion is approved."

Concerning the future course of his own party, Fuwa said that the JCP will appeal to swing voters -- who constitute half of the some 7 million people who voted for the JCP in the previous Lower House elections -- by revising its 1958 constitution.

At the 22nd party convention beginning Monday, the JCP is expected to officially adopt a resolution to recognize the existence of the Self-Defense Forces and drop a preamble that upholds Marxism-Leninism.

Political observers claim the party's change of course is aimed at paving the way for the JCP to join other parties to form a coalition government sometime in the future.

Fuwa, however, said, the revision is aimed at presenting the party's principle in wording that appeals to the public, stressing that the nature of the party is intact.