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TORONTO, Jan 30 (Reuters) - The Toronto Stock Exchange's main index trimmed losses but remained lower on Wednesday afternoon in a broad selloff as all eyes were on an interest rate decision from the U.S. Federal Reserve later in the day.
The index earlier slid by as much as 100 points, led lower by the resource-laden materials sector. Potash Corp of Saskatchewan was the biggest drag, shedding C$5.01, or 3.6 percent, to C$135.75, while the sector as a whole was off 1.1 percent.
Consumer staples and discretionary shares also weighed, with the sectors falling 1.6 percent and 1.3 percent respectively. Loblaw Cos (L.TO) was down C$1.51, or 4.6 percent, at C$31.54, while Metro MRUa.TO was off 26 Canadian cents, or 1.1 percent, to C$23.74 a day after it reported slightly higher first-quarter profit.
Investors were awaiting a U.S. interest rate decision, due at 2:15 p.m. (1915 GMT), with high hopes for a 50-basis-point cut.
"The expectation is for a half-point cut," said Lex Kerkovius, senior research analyst at McLean & Partners Wealth Management Ltd., in Calgary, Alberta. "If they don't give it to us, the market's going to go south in a big way."
The S&P/TSX composite index .GSPTSE was down 76.88 points, or 0.59 percent, at 12,969.55 with only one of its 10 main groups in positive territory.
The energy sector managed to hold on to gains, adding 0.6 percent, while Suncor Energy (SU.TO) was up after it said it will spend C$20.6 billion on expansions that will make it the biggest producer in Alberta's oil sands. Shares of Suncor gained C$2.49, or 2.7 percent, to C$93.59.
Data showing U.S. gross domestic product growth skidded in the fourth quarter added to the negative tone for the Toronto benchmark index, Kerkovius said.
"We really need (a 50 basis point cut) because based on that GDP number, the first quarter is going to be well into the negatives at the rate things are going," he said.
The heavyweight financial sector was lower, down 0.8 percent with Canadian Imperial Bank of Commerce (CM.TO) falling C$1.17, or 1.7 percent, to C$69.38, and Toronto-Dominion Bank (TD.TO) losing 69 Canadian cents, or 1 percent, to C$67.43.
$1=$0.99 Canadian Reporting by Leah Schnurr; Editing by Peter Galloway