The figure, a leading indicator of capital expenditure, may act as some solace to Japanese policymakers who are wary that Europe’s debt crisis, the US slowdown and the yen’s rise may stall recovery from the March 11 earthquake and tsunami.

The jump, much bigger than the market median forecast of a 4.9 percent rise, marks a rebound from an 8.2 percent slump in July and follows a string of disappointing data including exports and factory output in August.

Recent data fueled concerns that the rapid recovery from the disaster driven by companies restoring output was tailing off quickly, putting pressure on the central bank to consider further action after it eased its policy in August.

But Wednesday’s orders report showed the economy continued to benefit from the rebuilding effort, driven so far mainly companies’ drive to bring production back to pre-quake levels as Tokyo has yet to release the bulk of reconstruction funding.

“Although pessimistic views are emerging about the outlook for Japan’s economy due to an overseas slowdown and the yen’s strength, the economy’s gradual recovery is likely to be intact in the foreseeable future,” said Junko Nishioka, chief economist at RBS Securities in Tokyo. 

“So far, there is no convincing reason for additional (monetary) easing.”

Compared with a year earlier, core orders, increased 2.1 percent in August, against a 3.6 percent drop expected by economists. 

Manufacturers surveyed by the government in June forecast a 0.9 percent rise in core orders in the July-September quarter.

That result would be assured even if orders fell 10 percent in September, the government said.

“The data suggests that capital spending will likely be solid in the next few months,” said Minoru Masujima, head of business statistics at the Cabinet Office. 

He said August rise was driven largely by orders for electrical machinery and information and communication equipment.

Still, faltering overseas growth and fears that the global economy may slide back into recession mean it is only a matter of time before export-reliant Japan feels the pinch, economists say.

“The greatest risk for the Japanese economy is whether the global economy actually falls into a recession,” said Takeshi Minami, chief economist at Norinchukin Research Institute.

“If it’s just a slowdown, then the Japanese economy could be supported with reconstruction demand expected at the start of the new year. But if exports drop, then it would be difficult to support the economy merely with reconstruction demand.” 

Overseas machinery orders jumped nearly a third in August from the previous month, its biggest gain since June 2009, but the government kept its view that external demand remained weak and said a rise in a single month did not change that assessment. 

The Bank of Japan’s closely watched tankan corporate survey showed big firms were cautious and planned to increase capital spending by only 3 percent in the fiscal year to March 2012, less than the 4.2 percent projected by markets.

The Japanese economy has probably emerged from a recession triggered by the March disaster, but growth remains modest with analysts expecting a bigger slowdown in the final months of the year than previously thought.

The central bank kept monetary policy unchanged on Friday, holding off on tapping its depleted policy arsenal for now.

The government aims to submit to parliament this month bills to implement a $156 billion extra budget and tax hikes to fund post-disaster reconstruction, but their enactment is far from certain as combative opposition parties control the upper house and can block bills.