* MSCI Asia ex-Japan down 0.2 pct, Nikkei off 0.5 pct
* RBA rate cut, huge trade deficit keep Aussie pressured
* China official services PMI slows
* China, South Korea on holidays
* European shares likely mixed
By Chikako Mogi
TOKYO, Oct 3 (Reuters) - The dollar firmed while most riskier assets fell on Wednesday as data from China and Australia deepened gloom about the global economic outlook, further reducing risk appetite already hurt by uncertainty about the timing of Spain's request for a bailout.
U.S. stock futures eased 0.2 percent, suggesting a weak start on Wall Street, while financial spreadbetters expect European bourses to open mixed.
Predictions from financial spreadbetters for London's FTSE 100, Paris's CAC-40 and Frankfurt's DAX ranged from a 0.1 percent rise to a 0.2 percent drop.
Demand for the safe-haven dollar pushed the index measuring the dollar against a basket of six major currencies up 0.1 percent, and lifted the greenback to a 1-1/2 week high of 78.31 yen.
The euro eased 0.2 percent to $1.2896. It has come off a three-week low of $1.28035 touched on Monday but is drifting away from a 4-1/2 month high of $1.31729 seen in mid-September.
In Australia, the nation's trade deficit blew out to its widest in 3-1/2 years in August, weighing on the local currency and paring gains for equities. Falling prices for iron ore and coal on weak demand from China has eroded export earnings.
The Australian dollar slipped 0.5 percent, extending losses to a one-month low of $1.0211.
Australian shares rose 0.2 percent after climbing as much as 0.5 percent to hit a 14-month high on the Reserve Bank of Australia's move to cut interest rates a day earlier to defend the local economy against global headwinds.
China's official purchasing managers' index for the services sector fell to 53.7 in September from 56.3 in August as growth in the country's manufacturing industry stabilised at a slower pace, putting the world's second-largest economy on course for a seventh straight quarter of slowdown.
"It's hard to get bullish when the numbers are so bad, especially in China and the euro zone," said Tony Nunan, an oil risk manager at Mitsubishi Corp, referring to weak manufacturing data released this week.
The Asian Development Bank also cut most of its 2012 and 2013 growth estimates for developing Asia on Wednesday, citing the impact of the slump in global demand on China and India.
The MSCI index of Asia-Pacific shares outside Japan was down 0.2 percent while Japan's Nikkei average finished down 0.5 percent.
Hong Kong's Hang Seng index, which resumed trading after a holiday weekend, climbed 0.2 percent. Markets in China and South Korea are closed for holidays on Wednesday.
Analysts say markets nevertheless have become more resilient since last month after the U.S. Federal Reserve launched an aggressive stimulus package and the European Central Bank announced a programme to buy bonds of euro zone states which ask for assistance.
"Ever since these steps are taken, tail risks receded, market sentiment improved and market reactions to negative news became less acute than before," said Junya Tanase, chief FX strategist at JPMorgan in Tokyo.
"But there is no trend emerging as markets have not had a convincing assessment about risk for months," he said.
He said markets have priced in weak U.S. economic figures since disappointing August jobs data which preceded the Fed's action, adding that if ADP payroll data and the Institute for Supply Management's September non-manufacturing index came in as positive surprises, that could boost stocks and lift risk currencies against the yen.
Spanish Prime Minister Mariano Rajoy said on Tuesday a request for European aid was not imminent, denying a report Madrid could apply for help as soon as this weekend.
Spain's debt-saddled regional governments have magnified the burden on a central government already faced with its own huge deficit, pressuring the country's borrowing costs in open markets.
Market players are waiting for the Eurogroup meeting next Monday for potential progress on Spain. Ratings agency Moody's also said it will announce the results of a review of Spain's sovereign debt rating, currently just one notch above junk status, some time this month.
Other central bank policy meetings scheduled this week include ones for the ECB, the Bank of England and the Bank of Japan.
U.S. crude fell 0.2 percent to $91.72 a barrel and Brent fell 0.4 percent to $111.08.
Asian credit markets were subdued, with the spread on the iTraxx Asia ex-Japan investment-grade index tightening marginally by one basis point.