The Democratic Party of Japan, the largest opposition party, is planning a no-confidence motion against Prime Minister Keizo Obuchi's Cabinet over Monday night's Upper House panel vote on wiretapping bills.

Meanwhile, Liberal Party chief Ichiro Ozawa said Tuesday evening that he will make a decision "in a day or two" over whether his party will pull out of its coalition with Obuchi's Liberal Democratic Party because of differences over a pending bill to cut 50 proportional representation seats from the Lower House.

Even if the Liberals pull out of the alliance, however, a no-confidence vote against Obuchi is likely to be voted down by the LDP and New Komeito, which intends to join the coalition; New Komeito and the LDP form a comfortable majority in both chambers of the Diet.

On Tuesday morning, senior DPJ officials including party chief Naoto Kan confirmed their plan to submit a no-confidence motion against Obuchi to prevent enactment of a set of bills that will allow law enforcement authorities to wiretap communications while investigating organized crime.

The controversial bills were railroaded through the Upper House Judicial Affairs Committee the night before by the LDP, the Liberal Party and New Komeito amid fierce protests from opposition legislators.

The Upper House was initially scheduled to open its plenary session Tuesday morning but was unable to do so due to strong protests from the DPJ, the Social Democratic Party and the Japanese Communist Party. Ruling and opposition camp lawmakers continued talks into Tuesday night on when to open the plenary session.

The LDP, Liberal Party and New Komeito were still hoping to put the legislation to a vote by the full Upper House later in the night.

To deter such a move, however, the DPJ said it would submit a motion requesting that the chairman of the committee, Kiyohiro Araki, a New Komeito legislator, be removed from his position. The SDP and JCP were expected to join the DPJ in the move.

The opposition camp also threatened to submit the no-confidence motion to the House of Representatives and a resolution of censure against Obuchi in the House of Councilors before the current regular Diet session ends Friday.

During Monday's Upper House committee debate, while Yoriko Madoka of the DPJ was posing questions to Araki around 9 p.m., an LDP member suddenly proposed that the debate be terminated for a vote.

In the ensuing turmoil, members of the LDP, the Liberal Party and New Komeito, who form a majority on the committee, approved the proposal by raising their hands and then proceeded to endorse the bills in the same way, Araki later told reporters.

But opposition members protested that they could not properly hear the proceedings amid the noisy confusion, saying they would not recognize the vote as valid.

As the ruling and opposition camps continued on-and-off talks throughout Tuesday over the handling of the wiretapping bills, the talks between the LDP and the Liberal Party seeking a compromise on the Diet seat-reduction bill made little progress.

Ozawa, who has been threatening to leave the coalition if the LDP should fail to honor its promises over the legislation, reportedly told a meeting of Liberal Party lawmakers that he would make a decision "within a day or two."

In the meeting, the Liberal Party lawmakers agreed to leave all decisions on the issue up to Ozawa, party officials said.

In a meeting Monday, Obuchi and Ozawa reaffirmed that they would try to resolve the dispute over the plan to reduce by 50 the 200 proportional representation seats in the 500-seat lower house.

The proposed cuts are part of a policy agreement reached by the two parties before they launched the coalition in January. But the LDP is reluctant to have the Diet pass the bill because of objections from New Komeito.