Shanghai slides 0.9%
China's benchmark index retreated further from the previous session's three-month high thanks to declines in drug makers.
News that a local firm has been caught up in the nation's corruption probe, the first accusation aimed at a Chinese drug maker, spooked the sector. Shenzhen Neptunus lost 2 percent while both Guilin Layn Natural and Lukang Pharmaceutical lost 1.7 percent each.
Airlines lent some support to the index. China Eastern Air surged nearly 7 percent while Hainan Airlines rose 2 percent after Goldman Sachs analysts said that domestic airline stocks will benefit from Shanghai's free-trade zone in a research note.
Nikkei up 0.1%
Japan's benchmark index erased earlier losses to crawl back into positive territory as the yen weakened 0.3 percent against the greenback following a Nikkei report that President Obama is set to name Lawrence Summers as the next chairman of the Federal Reserve.
Sharp was the index's worst performer, lower by nearly 5 percent on news that it will issue new shares in public share offering to raise as much as $1.5 billion.
The rest of exporters were mixed camera maker Konica Minolta down 3 percent while battery maker GS Yuasa rose over 2 percent.
Reports that Prime Minister Shinzo Abe will raise the 5 percent sales tax to 8 percent from next April weighed on risk appetite. Media also reported sources as saying that Abe has ordered an economic stimulus package that could total as much as $50 billion to cushion the tax hike's impact.
Tokyo financial markets will be shut on Monday for a national holiday.