TOKYO TOKYO (Reuters) -- For all the solidarity Japan's opposition parties have offered the government as it grapples with a double disaster, few expect an end to the infighting that has hobbled policymaking and crucial budget bills.

Just hours before Friday's devastating earthquake struck the country, Prime Minister Naoto Kan -- deeply unpopular and accused of illegally receiving campaign funds -- was rebuffing calls from an emboldened opposition for his resignation.
That came after weeks of political skirmishing that had prevented Kan from crafting policies to fund the rising costs of a fast-aging society, curb public debt twice the size of the economy, and spur growth as the population shrinks.
But on Sunday, in a rare moment of reconciliation, the ruling Democratic Party of Japan (DPJ) and its main rival agreed to discuss a temporary tax increase to fund what is likely to be billions of dollars in disaster relief.
Nuclear authorities are scrambling to contain what could be the world's worst nuclear disaster in 25 years after an explosion at a reactor, while local media said the death toll from the quake and tsunami looked likely to rise above 10,000.
However, sniping over the government's handling of the humanitarian and nuclear reactor crises triggered by the quake, is a telling sign already that the truce will not last long.
""If it looks like things are subsiding, critics of (Kan's) Democratic Party will feel emboldened,"" said Sophia University professor Koichi Nakano. ""If they don't succeed (in averting a nuclear disaster), they will get a truce but be criticized sometime later.""
Despite calls for national unity by politicians and media alike since the crisis blew up, opposition leaders have already accused the government of sloppy disclosure about the accident at the nuclear plant in Fukushima. ""It took five hours after the explosion … before a response was issued,"" Japan Communist Party's Akira Kasai said in a TV debate. ""That is not good.""
Domestic media echoed the criticism of the government, which is led by a party that swept to power for the first time less than two years ago.
""Crisis management is incoherent,"" blared a headline in the Asahi newspaper, charging that the government was slow to disclose information about the quake-stricken nuclear facility and to expand the evacuation area around it.
Equally troubling for Kan, who took power last June as Japan's fifth premier since 2006, were mutterings from rivals inside his own party, many of whom had already wanted him to quit to repair the DPJ's battered fortunes.
""Every time they repeated 'stay calm' without giving concrete data, anxiety increased,"" the Asahi quoted a veteran DPJ lawmaker as saying.
Kan's handling of a crisis he himself has branded as Japan's biggest since World War Two, may do little to lift voter support, which was already languishing at around 20 percent after perceived policy flip-flops and diplomatic missteps during his and his predecessor's short terms in office.
The Democrats are trying to avoid a re-run of the government bumbling after a 1995 temblor that killed more than 6,400 people in the western port of Kobe, swiftly mobilizing 50,000 troops and other rescue teams to the vast devastated areas