Dec 11 (Reuters) - Canada’s main stock index fell on Friday, weighed down by weakness in energy stocks, while concerns over delays to a new U.S. stimulus package further dented sentiment. * The energy sector dropped 1.1% as U.S. crude prices fell 0.1% a barrel, while Brent crude lost 0.3%. * Meanwhile, U.S. House Speaker Nancy Pelosi on Thursday raised the possibility of U.S. stimulus negotiations dragging on through Christmas. * At 09:37 a.m. ET (14:37 GMT), the Toronto Stock Exchange’s S&P/TSX composite index was down 72.79 points, or 0.41%, at 17,520.55. * Energy producer Enerplus Corp fell 3.8%, the most on the TSX, and the second biggest decliner was cancer drug developer Trillium Therapeutics Inc, down 3%. * The ratio of Canadian household debt-to-income narrowed to 170.9% in the third quarter from a revised 172.1% in the second quarter, Statistics Canada said. * The financials sector slipped 0.5%, while the industrials sector fell 0.3%. * The materials sector, which includes precious and base metals miners and fertilizer companies, lost 0.3%. * On the TSX, 62 issues rose, while 151 issues fell in a 2.44-to-1 ratio favoring the losers, with 15.64 million shares traded. * The largest percentage gainers on the TSX were Transcontinental Inc, which jumped 5.7% after multiple brokerages raised the price target of the printing company, and lumber provider Interfor Corporation, which rose 1.8%. * The most heavily traded shares by volume were Canadian Natural Resources Limited , BCE Inc, and Bombardier Inc. * The TSX posted four new 52-week highs and no new low. * Across all Canadian issues, there were 22 new 52-week highs and one new low, with total volume of 32.61 million shares. (Reporting by Amal S in Bengaluru; Editing by Vinay Dwivedi)