Shanghai blue chips slipped 0.4 percent following two days of gains. E-Mini futures for the S&P 500 were off 0.25 percent.
Risk appetites had soured after British lawmakers crushed Prime Minister Theresa May's European Union divorce deal, forcing parliament to decide within days whether to back a no-deal Brexit or seek a last-minute delay.
Lawmakers voted against May's amended Brexit deal by 391 to 242 as her last-minute talks with EU chiefs on Monday to assuage her critics' concerns ultimately proved fruitless.
Parliament will vote later Wednesday on whether to leave the EU with no deal, and if that fails, a further vote on Thursday will decide whether to extend the Brexit deadline.
"The vote today seems certain to go against the government as well," said David de Garis, a director of economics and market at National Australia Bank.
"Assuming the Thursday vote finds a majority in favour of an extension - as we expect - it will likely be of some comfort to sterling," he added. "It's still a fast moving environment, with political pressure at understandably extreme levels."
The pound could do with some comfort after a wild couple of sessions. It was last at $1.3085 GBP= , having been as high as $1.3296 and as low as $1.3017 so far this week.
U.S. INFLATION SLOWS
On Wall Street, Boeing Co shed another 6.1 percent for its biggest two-day drop since June 2009, as more countries grounded the company's 737 MAX 8 planes following Sunday's crash in Ethiopia, the second fatal crash in months.
The drop in Boeing pushed the Dow down 0.38 percent, even as the S&P 500 gained 0.30 percent and the Nasdaq .IXIC added 0.44 percent.
A soft U.S. inflation report for February burnished bonds while tarnishing the dollar. Annual consumer price inflation slowed to its lowest since September 2016 at 1.5 percent.
The data merely reinforced expectations the Federal Reserve will stay patient on rates and could even sound more dovish at its policy meeting next week.
Yields on U.S. 10-year notes duly declined to a 10-week low at 2.596 percent, while the dollar idled at 96.956 against a basket of currencies.
The dollar drifted off to 111.18, while the euro climbed to $1.1289 and away from last week's 20-month trough of $1.1174.
In commodity markets, the dip in the dollar helped gold reach its highest in two weeks and it was last at $1,304.11 per ounce.
Oil prices edged up on tightening global supply after a Saudi official said the kingdom plans to cut oil exports in April, while the U.S. government reduced its forecast for domestic crude output growth.
U.S. crude was last up 20 cents at $57.07 a barrel, while Brent crude futures added 11 cents to $66.78.
(Reporting by Wayne Cole Editing by Darren Schuettler) ((firstname.lastname@example.org; +61 2 9321 8166; Reuters Messaging: email@example.com; twitter.com/swatisays))
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