(Reuters) -- Asian shares eased Thursday as investors turned increasingly cautious with hopes of stimulus action by central banks fading ahead of a European Central Bank's meeting later in the day and after the U.S. Federal Reserve took no action a day earlier.

MSCI's broadest index of Asia-Pacific shares outside Japan <.MIAPJ0000PUS> was down 0.2 percent while Japan's Nikkei stock average <.N225> opened flat. .T

"Expectations (of U.S. stimulus) weren't high but the market can't help but feel at least a little disappointed, although many investors are still willing to stay on the sidelines until the later ECB meeting provides a clearer direction," said Lee Young-gon, an analyst at Hana Daetoo Securities.

The U.S. stock market and U.S. Treasury debt prices fell while the dollar rallied against the euro and yen on Wednesday after the Federal Reserve took no new monetary stimulus after a two-day policy meeting ended.

But the Fed kept the door open for further bond buying, known as quantitative easing, to help a U.S. economic recovery that it said had lost momentum this year, a change of tone from its previous assessment in June when Fed officials said the economy had been "expanding moderately.

Investors will now focus on the annual central bankers' meeting at Jackson Hole, Wyo., on Aug. 31 for signs of possible Fed action, said Andrew Wilkinson, Chief Economic Strategist at Miller Tabak & Co.

"In the meantime it's over to Frankfurt to see what ECB's Mario Draghi has to say," said Wilkinson.

The dollar steadied against the yen around 78.40 yen, recovering from a two-month low of 77.90 yen hit on Wednesday.

The euro traded up 0.1 percent at $1.2234, off a three-week high of $1.2390 touched on Friday and above a two-year low around $1.2042 reached last week.

Markets have been hoping the ECB would resume its bond buying, called the Securities Market Programme (SMP), to help drive down borrowing costs for Italy and Spain which had soared to critical levels seen unsustainable for their economies.

Germany's Sueddeutsche Zeitung newspaper reported that ECB President Mario Draghi will unveil a two-pronged approach on Thursday - a concerted action using both the ECB and the future euro rescue fund European Stability Mechanism - to buy bonds from Spain or Italy.

"The reactivation of SMP is not in our base scenario; hence, we expect the market to be disappointed," Barclays Capital analysts said in a research note. "We believe this likely disappointment will continue to favour our short EURUSD positions for the week," they said.

Data released on Wednesday failed to give a clear direction for the U.S. recovery, giving ground for the Fed's prudence.

The Institute of Supply Management index on U.S. manufacturing activity shrank for a second month in a row in July, but reports on private employment and construction spending both suggested the economic deterioration since the first quarter was not as severe as some feared.

They preceded a key nonfarm payrolls due on Friday, which is expected to show a rise of 100,000 in July, with the unemployment rate staying unchanged at an elevated 8.2 percent.

Dashed hopes for a third round of U.S. quantitative easing weakened gold, as printing more money would have reduced the dollar's value and cheapened dollar-based gold while feeding future inflation risks and boosting its inflation hedge appeal.

Spot gold inched up 0.2 percent to $1,601 an ounce on Thursday while Brent crude futures eased 0.2 percent to $105.73 a barrel and U.S. crude fell 0.2 percent to $88.74 a barrel.

Asian credit markets firmed slightly early on Thursday, with the spread on the iTraxx Asia ex-Japan investment-grade index narrower by 1 basis point.

(Additional reporting by Joonhee Yu in Seoul; Editing by Michael Perry)