* TSX falls 60.55 points, or 0.48 percent, to 12,480.26 * Nine of 10 main sectors decline * Energy sector drops 1 percent By John Tilak TORONTO, Jan 7 (Reuters) - Canada's main stock index stumbled on Monday, led by mining and energy stocks that were pulled down by declining resource prices, as investors focused on the upcoming fourth-quarter earnings season. The resource-heavy market in Toronto pared some of the robust gains made in the previous week, when the index hit a nine-month high after a landmark U.S. budget deal. "The markets are coming off a hangover of feeling good from last week," said Barry Schwartz, vice president and portfolio manager at Baskin Financial Services. "Until we get a good feel on the fourth-quarter earnings and the guidance for first-quarter earnings, the market will probably trade sideways," he added. At midmorning, the Toronto Stock Exchange's S&P/TSX composite index was down 60.55 points, or 0.48 percent, at 12,480.26. Nine of the 10 main sectors on the index were in the red. The energy sector, down nearly 1 percent, slipped with lower oil prices and played a major role in leading the market lower. Suncor Energy Inc lost 1.2 percent to C$33.16, and Canadian Natural Resources fell 1.7 percent to C$29.64. The materials sector, which includes mining stocks, lost 0.7 percent. Fertilizer giant Potash Corp was down 1.1 percent at C$40.60, while Barrick Gold Corp fell 1.3 percent to C$33.72. Gold prices slipped as investors eyed the outlook for U.S. budget talks and the Federal Reserve's quantitative easing program. Investors were also taking in news that global regulators gave banks four more years and greater flexibility to build up cash buffers. However, the financial sector, the index's biggest, gave back 0.6 percent. Royal Bank of Canada was down 0.6 percent at C$60.68, and Toronto Dominion Bank slipped 0.7 percent to C$82.23. In company news, Canada's airlines flew fuller planes in December, with dominant carrier Air Canada and No. 2 rival WestJet Airlines reporting record monthly passenger levels. Air Canada shares were up 4.5 percent at C$1.85. WestJet shares inched up 0.15 percent to C$20.24.