Asian traders shifted cautiously on Tuesday with Chinese stocks swinging back and forth, while concerns grew about the future of the much-vaunted US tax reforms.

After months of gains across global equities, investors are taking a step back on unease that some valuations may be too high, though bitcoin continued its surge to new records and was on course to break the $10,000 mark.

Shanghai ended a volatile day up 0.3 percent, having lost more than three percent since Wednesday with mainland dealers spooked by Beijing's crackdown on risky dealing.

A warning from authorities last week about the sharp rise in one of the country's best-performing stocks added to worries. Analysts have also noted a lack of intervention by state-backed firms to support key issues, indicating a willingness to see prices fall to cool the market.