Although most Japanese are critical of his handling of the nuclear crisis triggered by the deadly March 11 earthquake and tsunami, Kan might be hard to force out soon, not least because there’s no obvious successor in sight in a country that has had five prime ministers since 2006.

The political jockeying, however, could slow agreement on how to pay for rebuilding from the natural disasters that caused up to $300 billion in damage, a conundrum given that Japan’s public debt now equals twice its $5 trillion economy.

Public opinion polls show that most Japanese want a new prime minister, but many would prefer Kan to stay until the crisis at Tokyo Electric Power Co’s (TEPCO) quake-crippled nuclear plant is resolved. When that will be remains uncertain but it is likely to be many more months.

The debate over funding revolves around whether and when to raise taxes — and which ones — to ensure that the government bonds expected to be issued can be paid back.

About 70 percent of voters would accept a tax hike to pay for rebuilding northeastern Japan, a survey showed this week.

Many lawmakers, though, fear higher levies, including a rise in the five percent sales tax, would hit spending as the economy struggles to recover.

A fragile detente with opposition parties was brief, the main rival Liberal Democrats already back to their role before the March 11 quake of lambasting Kansas

Critics in the ruling party are also growing restive.

“Listening to the prime minister’s responses (in parliament), I was forced to think. No matter what is said, he always stresses that he was justified ... Such responses only invite a backlash, and I think it is only natural that there are calls to replace the premier,” Deputy Finance Minister Mitsuru Sakurai wrote in a blog this week.

Sakurai is from the region hit by the natural disaster.
 

Sakurai’s comments, analysts said, reflect dissatisfaction among ruling Democratic Party of Japan (DPJ) lawmakers with Kan, who took office last June and led the party to defeat in an upper house election a month later after clumsily floating a sales tax rise to fund bulging social welfare costs.

That left the ruling bloc without a majority in parliament’s upper house and needing opposition help to pass bills.

“Almost everyone except Kan’s direct supporters wants to replace him,” said independent analyst Hirotaka Futatsuki.

“The problem is, who is there to succeed him?“

Kan’s backers say the middle of a crisis is no time to change leaders, and point out that ditching the nation’s fifth leader in as many years would prompt ridicule from abroad.

“It is impossible to change prime ministers at such a time. Foreign countries would view that as abnormal,” Hajime Ishii, a DPJ upper house heavyweight, told Reuters this week.

Some analysts also say changing leaders now could be risky and add that, anyway, Kan is unlikely to step aside easily.

“If the nuclear crisis stabilized, he would have a justification to resign,” said Waseda University professor Tetsur Kato. “But he might be encouraged to stay on.”

With no guarantee, however, that TEPCO can achieve its timeline of stabilising the Fukushima reactors by the end of the year, some of Kan’s critics say they can’t wait.

“Nothing is getting done at all,” said one DPJ source, adding that moves to oust Kan would likely heat up after an initial extra budget worth 4 trillion yen was enacted in May.

That package will be followed by others and a failure to forge agreement on funding could prove Kan’s downfall.

“Government bonds will have to be issued. The problem is a tax increase,” said Keio University professor Yasunori Sone.

“The people will accept a tax hike but if Kan is inept and can’t pass the second extra budget, he may have to resign.”

Who would get the job next, though, is hard to predict. Chief Cabinet Minister Yukio Edano, the face of Japan as it has battled the disasters, topped a list of politicians voters want to see exercise clout, but analysts say he may be too green.

Edano’s predecessor, Yoshito Sengoku, could be another possibility but might have trouble uniting the party. The group led by party powerbroker Ichiro Ozawa, himself tainted by a funding scandal so unlikely to run, has no clear contender.