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TORONTO, March 1 (Reuters) - Canada's main stock index fell to a more than two-week low on Thursday, weighed by declines for auto parts, railroad and steel companies as global investors worried about the impact of more protectionist trade policies proposed by U.S. President Donald Trump.
* The Toronto Stock Exchange's S&P/TSX composite index closed down 48.73 points, or 0.32 percent, at 15,393.95, its lowest close since Feb. 14.
* Seven of the index's 10 main groups ended lower.
* Stocks on Wall Street also fell, after Trump said the United States would impose import tariffs on steel and aluminum, raising concern about higher prices and a trade war.
* Canada will retaliate if the United States imposes tariffs on Canadian steel and aluminum products, Foreign Affairs Minister Chrystia Freeland said.
* Steel producer Stelco Holdings Inc fell 6.3 percent to C$23.96.
* Shares of trade-sensitive auto parts and railroad companies also lost ground, with Magna International falling 2.7 percent to C$68.72 and Canadian National Railway Co down 1.8 percent at C$97.49.
* The overall industrials group fell 0.8 percent, while the energy group declined 0.7 percent as oil prices fell.
* U.S. crude oil futures settled 1.1 percent lower at $60.99 a barrel, under pressure from a retreating stock market and worries about surging U.S. crude output.
* Toronto-Dominion Bank rallied after reporting quarterly earnings that beat market expectations. Its shares rose 1.2 percent to C$74.92.
* Shares of Canopy Growth Corp rose 9.5 percent to C$29.96. The chief executive officer of the marijuana producer said the company would list on the U.S. Nasdaq exchange "in due course."
* The materials group, which includes precious and base metals miners and fertilizer companies, rose 0.2 percent.
* Gold futures rose 0.2 percent to $1,318.1 an ounce.
* The TSX was posting four new 52-week highs and 18 new lows. (Reporting by Fergal Smith; Editing by Peter Cooney)