TOKYO - Japan's biggest opposition party plans to submit a no-confidence motion to parliament, its leader was quoted as saying on Thursday, piling pressure on unpopular Prime Minister Naoto Kan's as he struggles to contain a nuclear crisis.
It remains unclear if a motion against Kan and his cabinet would gain enough support from other groups, including rebels in Kan's own Democratic Party (DPJ), to force the premier to resign or call a snap election.
A no-confidence motion would need backing from about 75 of the Democratic Party's more than 300 lawmakers in parliament's powerful lower house.
"The feeling is spreading among the people that the Kan government is reaching the limits of dealing with recovery and rebuilding," the Nikkei newspaper quoted Sadakazu Tanigaki, head of the opposition Liberal Democratic Party, as saying.
"A no-confidence motion is the biggest weapon of an opposition party ... and we have a responsibility to submit one since it is such a problematic government," he added. But he stopped short of saying when the motion would be submitted.
Kan, sworn in last June, is already Japan's fifth prime minister in as many years and the second since his Democratic Party of Japan (DPJ) swept to power for the first time in 2009, promising to change how the country is governed after more than half a century of almost non-stop rule by the Liberal Democrats.
Already unpopular before the March 11 disasters struck, Kan has come under fire for his handling of the crisis at Tokyo Electric Power Co's Fukushima plant and his ratings are hovering below 30 percent.
Kan, now in Europe for a Group of Eight meeting and a Japan-European Union summit, will be fighting on two fronts when he returns on Sunday.
The LDP and its erstwhile partner, the smaller New Komeito Party, are eager to return to power, while Kan's rivals in his own party dislike his sometimes abrasive style, are irritated over his policy shift away from campaign pledges to spend more money on consumers and worry his low voter ratings will scuttle their chances at the next election, which must be held by 2013.
"There is no serious policy disagreement," said Steven Reed, a political science professor at Chuo University in Tokyo.
"They agree on what they should do, but they disagree on who should do it." Kan wants reforms of the social security system and tax code, including a likely rise in the 5 percent sales tax, to fund the costs of a fast-ageing society. The LDP generally agrees such reforms are needed.
Analysts and political insiders said it was still a big question whether the LDP could win over enough disaffected Democrats for the no-confidence motion to pass.
"It's not that easy to gather so many votes," said one DPJ source. "It's hard to see, but it's not impossible."
Kan could call a lower house election if a no-confidence motion were to pass, but that would risk a backlash from voters who want politicians to concentrate on the nuclear crisis and on rebuilding northeast Japan, where the quake and tsunami left 25,000 dead or presumed dead and devastated the region. Tens of thousands of people are still living in evacuations centres.
Nor is it clear who would replace Kan if he were to quit.
Among the names floated are Tanigaki, a former finance minister who lacks an image as a strong leader or a DPJ elder such as 79-year-old Kozo Watanabe, who might head of a new coalition until a general election next year.