Japan’s parliament will on Tuesday begin an intense debate about the merits of a bill to extend the country’s refuelling operations in the Indian Ocean, Tokyo’s contribution to the US-led “war against terrorism” in Afghanistan.

But what they will really be discussing is the future of the new administration of Yasuo Fukuda, still barely a month old.

Foreign diplomats say the debate is crucial. It will determine whether Japan can continue to participate in the Afghan operation when Washington is worried about any signs of cracks in its anti-terror coalition.

Second, there is growing concern that Japan’s ability to run an effective presidency of the Group of Eight next year could be impaired if the government is distracted by what is likely to become a battle for its own survival.

These may seem exaggerated claims for a bill that would extend beyond November 1 the supply of fuel by Japanese naval vessels in an operation that is little known outside the country. If Japan’s opposition is to be believed, it is even little known by Afghan leaders themselves.

But difficulties in passing the bill through a parliament, whose upper house is now controlled by the opposition Democratic Party of Japan, was the stated reason for the sudden resignation of Shinzo Abe from the premiership in September.

Mr Fukuda’s Liberal Democratic party, which controls the more powerful lower house, can theoretically use its two-thirds majority to blast the legislation through – although not in time to prevent a hiatus in operations, which will have to be suspended in just over a week. But many in the LDP are wary of antagonising an opposition whose huge victory in July’s election means it is likely to dominate the upper house for six years.

Taku Yamasaki, chairman of the LDP’s foreign affairs research commission, said recently: “We want to pass this bill as soon as possible. But, with the DPJ against it, frankly the prospects for passage look very dark.” Overriding the DPJ could precipitate an early dissolution of parliament, he warned.

The LDP’s calculations have been complicated by two factors. One is that the defence ministry misled the government about the amount of fuel supplied to allied ships and, possibly, the use to which those supplies were put. The opposition has suggested that some fuel donated by Japan may have been used in Iraq. That would not only contravene the scope of the emergency bill but also, potentially, Japan’s pacifist constitution.

The defence ministry on Monday apologised for misleading politicians about the amount of fuel supplied. Mr Fukuda, as chief cabinet secretary in May 2003, made erroneous public comments based on those false reports.

Compounding the government’s misery is a brewing scandal over defence procurement contracts, not exactly the first. The DPJ is pushing the government to call parliamentary hearings over alleged collusion between the defence ministry and one contractor. Government officials were on Monday indicating they might agree to an inquiry, even though this would be bound to delay the progress of its anti-terror bill.

The DPJ has leapt on the alleged scandal as a reason for postponing its own proposal for an alternative anti-terror bill, which may involve sending ground troops to Afghanistan as part of Nato-led International Security Assistance Force operations. Ichiro Ozawa, the DPJ’s leader, said he opposed refuelling operations because they had no United Nations mandate.

Political analysts say the DPJ, which can keep hold of the bill in the upper house for up to 60 days, hopes to jam up parliamentary business in order to force an early election.

It may pass a non-binding censure motion in an effort to embarrass Mr Fukuda into going to the electorate for a fresh mandate.

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