CANADA FX DEBT-C$ hits 10-week low on U.S. tariff threat, GDP miss

(Adds strategist quotes and details throughout; updates prices)

* Canadian dollar at C$1.2887, or 77.60 U.S. cents

* Loonie touches its weakest since Dec. 19 at C$1.2915

* Bond prices lower across the yield curve

* 10-year yield touches lowest intraday since Jan. 17

TORONTO, March 2 (Reuters) - The Canadian dollar weakened against its U.S. counterpart on Friday, adding to 10-week lows as data showed slower-than-expected growth in the domestic economy and investors braced for planned U.S. tariffs on steel and aluminum.

At 4 p.m. EST (2100 GMT), the Canadian dollar was

trading 0.4 percent lower at C$1.2887 to the greenback, or 77.60 U.S. cents. It touched its weakest level since Dec. 19 at C$1.2915. U.S. President Donald Trump unveiled the tariffs on Thursday but did not make clear whether they would apply to Canada, which is the largest supplier of both steel and aluminum to the United States. "Presuming the sanctions cover Canada, it hurts," said Greg Anderson, global head of foreign exchange strategy in New York. "This is a fluid situation ... there is still some chance that Canada gets exempted." Trump's threats to unleash a trade war over steel crushed any hopes of substantial progress in talks to rework the North American Free Trade Agreement. Canada sends 75 percent of its goods exports to the United States. A collapse of NAFTA could hurt its economy, which grew of economists' forecasts for 2.0 percent. "It is just consistent with an economy that is seeing growth converge back to its trend pace," said Andrew Kelvin, senior rates strategist at TD Securities. Still, money markets expect another interest rate hike from the Bank of Canada by July. The central bank raised its benchmark interest rate in January to 1.25 percent, its third hike in six months. The price of oil, one of Canada's largest exports, rose on Friday, but posted its first weekly fall in three weeks.

Speculators cut bullish bets on the Canadian dollar for the third straight week, data from the U.S. Commodity Futures Trading Commission and Reuters calculations showed. As of Feb. 27, net long positions had fallen to 22,220 contracts from 23,127 a week earlier. Canadian government bond prices edged lower across the yield curve in sympathy with U.S. Treasuries after the Bank of Japan's chief hinted at a possible exit from its ultra-easy policies.

The 10-year fell 19 Canadian cents to yield

2.201 percent. Intraday, it had touched its lowest since Jan. 17 at 2.155 percent. The gap between Canada's 10-year yield and its U.S. equivalent widened by 4.1 basis points to -66.7 basis points, its widest since June 26.

(Reporting by Fergal Smith; editing by Grant McCool)