Prime Minister Yoshiro Mori survived a no-confidence motion against his Cabinet early Tuesday after his rivals in the Liberal Democratic Party -- primarily Koichi Kato and Taku Yamasaki -- reneged on their pledge to support the motion submitted by the opposition camp.

The motion, proposed by the Democratic Party of Japan, the Liberal Party, the Japanese Communist Party and the Social Democratic Party, was defeated in the House of Representatives by 237 votes to 190.

Fifty-two lawmakers failed to show up for the vote. They included 21 members of the Kato faction and 17 members of Yamasaki's, including the two leaders.

Speaking to reporters after the predawn vote, Mori vowed to carry on and not step down.

"While I accept what happened with full modesty, I will put all my heart and soul into the various tasks facing the Cabinet," he said.

LDP Secretary General Hiromu Nonaka said LDP lawmakers who abstained from the vote would not be punished by the party.

Nonaka said he was glad to have avoided what he termed "a worst-case scenario" in which Kato and Yamasaki faction lawmakers backed the motion and brought about the breakup of the party.

Kato sparked the intra-LDP turmoil on Nov. 10 by calling on Mori to step down. Days later, he and Yamasaki vowed to support the no-confidence motion that the opposition had begun to brandish.

The two held their ground throughout their week-and-a-half uprising, saying they would not leave the LDP but instead hoped to revive it after ousting Mori.

Then on Monday night, shortly before deliberations on the motion began, they waved the white flag by saying they would stay away from the session.

Both Kato and Yamasaki apologized to the public early Tuesday for breaking their pledge and vowed to continue to fight for political reform.

"I want to offer sincere apologies for damaging many people's confidence. We lost this time because we were not well-prepared and lacked a suitable strategy," Kato told reporters after the motion was voted down in the plenary session.

"I'm sure it will require much time and work to restore people's confidence in our political system, but I'll take up the challenge of creating one in which every politician can freely express what he thinks," he claimed.

He declined to clearly explain why he skipped the session and the vote on the motion, merely saying, "Whatever I say now would be an excuse."

He later said he changed his mind about backing the motion because he feared that if he followed through on his pledge it would damage the unity of his faction.

Yamasaki said in the same news conference, "We did our best. But we were not up to the task" in terms of gathering enough support.

The pair's decision came after LDP leaders waged a fierce campaign to bring lawmakers around to their side in the vote. Kato's faction was split between those backing the motion and those who did not, including Finance Minister Kiichi Miyazawa.

The opposition has 190 seats in the 480-seat Lower House. Since the motion requires a majority of the chamber to succeed, the opposition needed 50 ruling bloc lawmakers to vote with them.

The absence of almost 40 members of Kato's and Yamasaki's factions who planned to support the motion ensured the LDP and its coalition partners, New Komeito and the New Conservative Party, had sufficient strength to defeat it.

Mori declined Tuesday to accept resignation offers by two parliamentary vice ministers belonging to the Kato and Yamasaki factions in the wake of the failed no-confidence motion.

Gen Nakatani, senior parliamentary vice minister at the Home Affairs Ministry, a member of the Kato faction, and Kisaburo Tokai, parliamentary vice minister of science and technology and a member of the Yamasaki faction, tendered their resignations Sunday evening in preparation for siding with their faction leaders' avowed support for the motion.

Nakatani and Tokai will remain in their posts, officials said.

Chief Cabinet Secretary Yasuo Fukuda said Tuesday that the LDP members who abstained from the no-confidence vote should now cooperate with the rest of the party and coalition members.

"The fact that the LDP was not split should be appreciated to begin with," he said.

He also said the rejection of the no-confidence motion does not necessarily mean the Mori administration has been fully endorsed.

"Since many people abstained from the vote, I cannot call it (a vote of full confidence)," Fukuda told a regular news conference. "We should humbly accept the fact that there were such absentees."

During an unofficial Cabinet meeting earlier in the day, Mori expressed gratitude that the ruling bloc united to vote down the no-confidence motion, Fukuda said.

If the motion had passed, Mori would have had to resign along with his Cabinet or dissolve the Lower House within 10 days for a general election.

Although Mori survived the motion, it may not put an end to his problems. LDP lawmakers in mainstream factions are concerned that they could receive a drubbing in the House of Councilors election next summer if the unpopular prime minister stays in his post, and may call for his resignation.

The vote on the no-confidence motion, initially planned for late Monday, was delayed until 3:30 a.m. following an interruption in the Lower House plenary session.

Monday's session broke for recess after NCP member Kenshiro Matsunami threw water at jeering opposition members during his speech against the motion.

Lower House Speaker Tamisuke Watanuki ordered Matsunami out of the session, but opposition parties, unhappy with Watanuki's handling of the incident, submitted a no-confidence motion against the speaker.

The motion was rejected.

The last time a no-confidence motion was passed was in 1993, when the Lower House approved the motion against then Prime Minister Kiichi Miyazawa's Cabinet with support from LDP rebels.

The move sparked a general election, which led to the formation of an anti-LDP ruling alliance.