imageTORONTO: Canada's main stock index opened lower on Tuesday as disappointing economic data and soft commodity prices weighed on the financial and natural resource sectors.

Government data showed the Canadian economy did not expand in July, breaking a six-month streak of consecutive gains.

Investors also fretted about geopolitical tensions in Hong Kong and the prospect of the US Federal Reserve raising interest rates.

The benchmark index looked on track to record its worst monthly decline since May 2012, set to lose about 4.4 percent in September.

“We've had a nice move on the TSX year-to-date," said Barry Schwartz, vice president and portfolio manager at Baskin Financial Services. “Sometimes you've got to take a break, and we're on a break."

He said investors should use the pullback as a buying opportunity but cautioned against purchasing commodity-related stocks.

Schwartz said he was seeing value in the financial, telecom and consumer sectors.

The Toronto Stock Exchange's S&P/TSX composite index was down 28.10 points, or 0.19 percent, at 14,948.82. Eight of the 10 main sectors on the index were in the red.

Financials, the index's most heavily weighted sector, slipped 0.4 percent. Bank of Nova Scotia declined 0.6 percent to C$68.80, and Bank of Montreal lost 0.6 percent to C$81.84.

The materials sector, which includes mining stocks, gave back 0.3 percent as the prices of gold, silver and copper traded lower. First Quantum Minerals Ltd shed 1.2 percent to C$21.45, and Potash Corp fell 0.5 percent, at C$38.77.

In corporate news, exchange operator TMX Group Ltd on Monday named Lou Eccleston as its new chief executive officer, to replace retiring CEO Tom Kloet. The stock was down 0.5 percent, at C$54.11.

Copyright Reuters, 2014