TOKYO (Reuters) - Asian stocks and the euro handed back gains and slipped on Thursday after the European Central Bank took a hard line stance on Greece's debt and dampened optimism towards a resolution to the saga.

Risk appetite, which had warmed earlier in the week on hopes that Greece would gain relief from its creditors, took a hit after the ECB pulled back its soft treatment of Greek debt and cancelled its acceptance of the country's bonds in return for funding.

MSCI's broadest index of Asia-Pacific shares outside Japan was down 0.1 per cent after climbing 1 percent the previous day. Japan's Nikkei, which surged 2 percent on Wednesday, dropped 0.5 per cent. South Korean and Australian stocks were also lower.

Investors also became more risk-averse as an extended rally in crude oil petered out. Wall Street snapped a two-day surge overnight, weighed by a slide in energy shares.

Crude oil plunged overnight in one of its biggest daily falls ever as record high U.S. oil inventories ended a four-day rally. In a "dead cat bounce" U.S. crude was last up 0.7 per cent at US$48.79 a barrel after sinking 9 per cent on Wednesday.

A monetary easing move by China late on Wednesday in an attempt to energise its sputtering economy failed to lift the cheerless mood in the region's equity markets.

"Although the move by PBOC does ease credit and may be beneficial to stimulating demand, it is also a clear sign that growth in China is declining at faster rate than previously thought and as such could have dampening effect on demand throughout the Asia region," Boris Schlossberg, managing director at BK Asset Management, wrote in a note to clients.

In currencies, the euro traded at US$1.1341, having fallen as far as US$1.1315. It has completely reversed a short-covering rally that lifted it to $1.1534 on Tuesday.

The US dollar was little changed at 117.29 yen, with the market awaiting the U.S. employment-related data later in the session as a preview to Friday's all important non-farm payrolls.