Canada's main stock index was down nearly 200 points in late-morning trading and U.S. stock markets also retreated as the stock market rally over the two days fizzled out.
The S&P/TSX composite index was down 194.89 points at 19,176.10 after gaining nearly 500 points on Tuesday.
In New York, the Dow Jones industrial average was down 340.03 points at 29,976.29. The S&P 500 index was down 55.09 points at 3,735.84, while the Nasdaq composite was down 220.05 points at 10,956.36.
The Canadian dollar traded for 73.08 cents US compared with 73.67 cents US on Tuesday.
The November crude contract was up US$1.18 at US$87.70 per barrel and the November natural gas contract was up three cents at US$6.87 per mmBTU.
The December gold contract was down US$13.00 at US$1,717.50 an ounce and the December copper contract was down two cents at US$3.47 a pound.