The banking sector <.SPTTFS> fell 0.2 percent as Canada's 10-year government bond yield touched 1.505 percent, its lowest in four months.

Higher bond yields would reduce the value of insurance companies' liabilities and increase net interest margins of banks.

Bank of Nova Scotia (>> Bank of Nova Scotia) was the biggest drag on the Toronto market, down 0.8 percent at C$78.11, followed by Royal Bank of Canada (>> Royal Bank of Canada), which declined 0.5 percent to C$97.32.

Traders were focused on the political environment after the United States launched cruise missile strikes on a Syrian air base. Russia warned on Friday that the move could have "extremely serious" consequences.

"Markets have been fairly complacent on the risk side," said Youssef Zohny, international client advisor at the StennerZohny Group of Morgan Stanley.

"So any sort of headline or geopolitical risk, I would say the market is more sensitive to some of those effects."

The Toronto Stock Exchange's S&P/TSX composite index <.GSPTSE> finished down 30.05 points, or 0.19 percent, at 15,667.13.

Six of the index's 10 main groups were lower. Even with Friday's small decline, the TSX ended the week up 0.8 percent, its second consecutive week of gains.

Despite higher commodity prices, both the energy <.SPTTEN> and materials <.GSPTTMT> sectors weighed on the index on Friday and were down 0.7 percent and 0.5 percent, respectively.

Barrick Gold Corp (>> Barrick Gold Corp) declined 0.9 percent to C$25.64 after Argentinian mining officials told the company it must overhaul environmental and operating processes at its Veladero mine following last week's cyanide solution spill.

Bank of Montreal (>> Bank of Montreal), Canada's fourth-biggest lender, said Chief Operating Officer Darryl White will step up to be chief executive in November, succeeding Bill Downe who will retire. The bank's shares edged up 0.3 percent at C$100.23.

Investors will start to turn their attention toward earnings season, with some corporate results coming out of the United States next week, said Zohny.

Given that stock valuations and earnings expectations have risen, there is a downside risk to the market in the near term unless a strong catalyst emerges, he said.

The market is up 2.5 percent for the year so far, extending the hefty 17.5 percent gain it saw in 2016.

(Reporting by Fergal Smith in Toronto and Leah Schnurr in Ottawa; Editing by James Dalgleish)