Dec 17 (Reuters) - Canada's main stock index fell at the open on Tuesday and was set to break its three-day winning streak, with shares of lumber products company Canfor Corp leading declines.
* At 9:35 a.m. ET (1435 GMT), the Toronto Stock Exchange's S&P/TSX Composite index was down 13.65 points, or 0.08%, at 17,042.71.
* Canfor Corp tumbled 21% after it rejected Great Pacific Capital Corp's proposal to take it private.
Reporting by Shreyashi Sanyal in Bengaluru; Editing by Vinay Dwivedi