* TSX down 62.64 points, or 0.41 percent, at 15,221.97
* Five of 10 main index sectors decline
* Canadian Natural, Suncor fall with oil price
By John Tilak
TORONTO, Feb 18 (Reuters) - Canada's main stock index slipped on Wednesday as a recent rally in the price of oil began showing signs of losing momentum, weighing on energy producers' shares.
Investors also followed news that Greece will submit a request to the euro zone to extend a "loan agreement" for up to six months. However, Germany said no such deal was in the works and Athens must stick to the terms of its existing international bailout.
Oil prices remained choppy, with investors increasingly concerned whether the recent gains were sustainable. They have gained about 35 percent since hitting multiyear lows in January, when worries about excess oil supply weighed on prices.
"We've used this downward volatility (in oil) opportunistically to try and pick away at favored positions within the sector," said Ian Riach, a portfolio manager and director of balanced portfolio management at Franklin Templeton Investments.
"We're trying to go in and find those names that we feel have been more heavily punished with the decline in the oil price than is justified," he added.
The Toronto Stock Exchange's S&P/TSX composite index was down 62.64 points, or 0.41 percent, at 15,221.97. Its decline followed gains in each of the six previous sessions.
While Riach favors equities over bonds, he is underweight in Canadian stocks in his institutional portfolio because he is more bullish about the U.S. market's prospects.
"The growth metrics in Canada aren't as robust as maybe they are in the U.S., and valuations were trading at levels that made a lot of Canadian companies vulnerable to earnings disappointments," he said.
Five of the 10 main sectors on the benchmark index were in the red on Wednesday.
Financials, the index's most heavily weighted sector, shed 1 percent. Bank of Nova Scotia fell 1.3 percent to C$66.51, and Toronto Dominion Bank gave back 1.4 percent to C$54.76.
In the energy sector, Canadian Natural Resources Ltd slipped 1.9 percent to C$38.80, and Suncor Energy Inc lost 0.5 percent to C$38.96. (Editing by Jonathan Oatis)