The Toronto Stock Exchange's S&P/TSX composite index ended down 113.16 points, or 0.6%, at 20,553.25, its lowest close since Aug. 26.

Wall Street also lost ground as investors looked past lower-than-expected inflation data, focusing instead on economic uncertainties and growing chances of a corporate tax rate hike.

"Any time people talk about those market-related taxes, that can definitely influence investors," said Colin Cieszynski, chief market strategist at SIA Wealth Management.

Underlying U.S. consumer prices increased at their slowest pace in six months in August, suggesting that inflation had probably peaked, although it could remain high for a while amid persistent supply constraints.

Investors have been concerned that a sustained rise in inflation could push the Federal Reserve into tightening policy earlier than signaled.

"They still got the issue that the Fed is probably going to have to start tapering because inflation is turning out to be more sticky and less transitory," Cieszynski said.

Canada's inflation report for August is due on Wednesday.

The TSX's energy group fell 1.3%, giving back some of the previous day's sharp gains, while the heavily weighted financials group was down 0.6%.

Shares of Teck Resources Ltd ended 4.9% higher after a report that the company is exploring options for its metallurgical coal business, including a sale or spinoff that could value the unit at as much as $8 billion.

Bombardier Inc unveiled an upscale variant of its strong-selling Challenger 350 business jet. Its shares fell 2.6%.

(Reporting by Fergal Smith; Additional reporting by Amal S in Bengaluru; Editing by Peter Cooney)

By Fergal Smith