* TSX up 19.80 points, or 0.13 percent, at 15,284.61
* Five of 10 main index sectors advance
* Restaurant Brands jumps 8.1 percent after posting results
By John Tilak
TORONTO, Feb 17 (Reuters) - Canada's main stock index edged higher on Tuesday as a jump in Restaurant Brands International Inc, following the fast-food chain's quarterly report, helped offset declines in the natural resource sectors after commodity prices weakened.
Worries about whether Greece will be able to secure a debt deal remained an overhang on the market. Talks between Greece and euro zone finance ministers over the country's debt crisis broke down on Monday when Athens rejected a proposal to request a six-month extension of its international bailout package as "unacceptable."
The benchmark TSX advanced for a sixth straight session and neared a five-month high before giving up some of those gains.
"I see more choppiness this year, both on the upside and on the downside," said Adrian Mastracci, portfolio manager at KCM Wealth Management.
Investors should "expect volatility. It's going to be with us," he added.
The Toronto Stock Exchange's S&P/TSX composite index closed up 19.80 points, or 0.13 percent, at 15,284.61. Five of the 10 main sectors on the index were higher.
Financials, the index's most heavily weighted sector, rose 0.7 percent. Bank of Montreal advanced 0.4 percent to C$78.97.
Shares of energy producers slipped, with oil prices staying volatile. Talisman Energy Inc was down 0.2 percent at C$9.47, and Suncor Energy Inc fell 0.6 percent to C$39.15.
Lower bullion prices pulled the gold-mining sector down 3.6 percent. Goldcorp Inc declined 3.9 percent to C$28.20, and Barrick Gold Corp lost 1.7 percent to C$14.87.
Restaurant Brands, formed out of Burger King's takeover of coffee and doughnut chain Tim Hortons last year, saw higher quarterly sales growth at both brands but posted a net loss due to one-time costs related to the merger. The stock jumped 8.1 percent to C$52.15. (Editing by Jonathan Oatis and Tom Brown)