Koichi Kato's revolt against Prime Minister Yoshiro Mori has fueled growing sentiment within the Liberal Democratic Party that the unpopular Mori should step down to avert a crisis that could severely split the ruling party.

How the LDP turmoil will be resolved remains unclear, but it appears certain that none of the players in the political game of chicken will survive unscathed. Even if the party elders decide to sack Mori, it does not mean Kato would be their next leader of choice.

Kato, a 61-year-old former LDP secretary general and currently head of the party's No. 2 faction, has burned his bridges by intensifying his anti-Mori pitch, warning he may back a no-confidence motion against the prime minister that the opposition camp has threatened to submit sometime toward the Dec. 1 close of the current Diet session.

Many LDP lawmakers wonder why Kato is suddenly challenging the party mainstream now. He has grown increasingly critical of Mori but until recently had ruled out the possibility of supporting a no-confidence motion against him.

Kato, a diplomat-turned-lawmaker who was the runnerup to the late Keizo Obuchi in last year's LDP presidential race, was at one time widely expected to take over from Mori -- possibly after the Upper House election next summer.

With popular approval ratings of the Mori Cabinet in newspaper polls dipping dangerously below 20 percent, however, Kato seems to have decided to take action on his own -- rather than just wait for his turn to wipe up the mess Mori leaves behind.

LDP schism takes shape

Whatever his intentions, the LDP appears on the verge of splitting up if Kato remains true to his word -- unless the party elders forestall his rebellion before the no-confidence motion is put to a Diet vote.

"They are playing a game of chicken. The (LDP's) mainstream factions want (Kato) to surrender, while Mr. Kato wants to prove he has enough clout to topple the government," said a senior official of New Komeito, the LDP's partner in the ruling coalition along with the New Conservative Party.

If Kato backs down and allows the Mori government to continue, he will face criticism for much ado about nothing and his political future could be doomed.

But a senior LDP lawmaker said such a "soft landing" is impossible, predicting the leadership of the party must undergo significant change to avoid a split.

For LDP bigwigs, defection or expulsion of rebel members must be avoided at a time when the LDP-led bloc barely holds a majority in both chambers of the Diet.

In 1993, the LDP fell from power for the first time in 38 years when it suffered a defection of lawmakers led by Ichiro Ozawa, who voted for a no-confidence motion against then Prime Minister Kiichi Miyazawa. It returned to power the following year -- but only in a coalition government under Socialist Prime Minister Tomiichi Murayama. The LDP had to wait until 1996 to elect its president, Ryutaro Hashimoto, as prime minister.

LDP unity, not Mori, first

One likely scenario to avoid defections would be for party elders to effectively sack Mori in exchange for Kato not supporting the no-confidence motion. Mori would be held responsible for the turmoil, and a party election would be held at an early date to pick his successor.

Even before Kato's revolt, many junior LDP lawmakers were expressing concern that the party could suffer in the Upper House election next summer if the unpopular Mori stays at the helm.

When the LDP's largest faction, led by Hashimoto, met Tuesday evening, some members reportedly said Mori should be removed and a party election held at an early date.

The top leaders of the Hashimoto faction -- LDP Secretary General Hiromu Nonaka and Mikio Aoki, secretary general of the LDP's Upper House members -- were among a handful of party elders who reportedly handpicked Mori when Obuchi collapsed in April. It is widely believed the faction holds the key to Mori's fate.

Still, it is eventually up to Mori whether he would agree to step down, since his current term as LDP president runs through September. Even if the Hashimoto faction opts to pull the rug out from under him, it will need to forge a consensus with other groups that have supported Mori, including the one led by the prime minister himself.

Mori, for his part, reiterated to reporters on his way to Brunei, where he is attending the Asia-Pacific Economic Cooperation forum summit, that he has no intention of resigning.

Should a party election be held, there is no guarantee that Kato would take Mori's place. The mainstream LDP factions, which currently hold a solid majority within the party, would probably field a candidate of their own to run against Kato.

Likely contenders would include Foreign Minister Yohei Kono, former Foreign Minister Masahiko Komura and Junichiro Koizumi, who chairs a faction led by Mori but has long been considered Kato's ally, according to party sources.

No-confidence showdown

So what if the turmoil drags on until the no-confidence vote is actually put to a Lower House vote?

Chances of the motion clearing the chamber will depend on whether Kato and his longtime ally Taku Yamasaki can win over at least 50 like-minded LDP members who would join hands with the 190-member opposition camp to forge a majority in the 480-seat chamber.

Although the Lower House members in the Kato and Yamasaki factions add up to 64, it appears unlikely that all of them would vote against Mori. Some senior Kato faction members who hold key government and LDP posts under Mori -- including Finance Minister Kiichi Miyazawa, LDP Executive Council Chairman Sadatoshi Ozato and party Diet affairs chief Makoto Koga -- are critical of Kato's revolt.

If they merely abstain from voting on the planned motion, as Kato initially indicated when he launched the rebellion last week, the LDP and its coalition partners would still be able to vote it down -- albeit by a slim margin.

Without the Kato and Yamasaki faction members, the LDP, New Komeito and the NCP will still hold 208 seats, outnumbering the opposition camp plus unpredictable independents and small groups.

Should the no-confidence motion be approved, Mori would have to either step down or -- more likely -- dissolve the Lower House and call a general election.

For their part, Kato, Yamasaki and their followers would probably face expulsion from the party.

"It is 100 percent unlikely that Kato will become (the next) prime minister while remaining in the LDP," a top LDP official said earlier this week. "But I don't know if Kato and the opposition camp have made an arrangement (for him to become the prime minister in a coalition with the opposition forces)."

The opposition, led by the DPJ, is split over Kato's sudden insurgence. While they admit his support for the planned no-confidence motion is welcome, they are also unclear about Kato's future plans, including his claim that he has no intention of leaving the LDP.

Kato has one reason to believe he can stay in the LDP even after backing the no-confidence vote against the party chief: He has seen it before.

In 1980, Kato was deputy chief Cabinet secretary under then Prime Minister Masayoshi Ohira when an opposition-proposed no-confidence motion was passed while anti-Ohira LDP factions abstained from a Lower House vote on the motion.

Ohira dissolved the chamber but died during the campaign for the subsequent general election. At that time, Mori belonged to one of the factions that boycotted the Lower House vote.

Opposition leaders say they want to wait and glean Kato's true intentions before submitting the no-confidence motion. The move could come as early as next week -- possibly after the 4.78 trillion yen extra budget for fiscal 2000 clears the Diet.