(Reuters) - Canada's main stock index opened lower on Tuesday weighed by heightening tensions in the Middle East and signs that the G20 meeting may generate little progress on U.S.-China trade.
* At 9:37 a.m. ET (13:37 GMT), the Toronto Stock Exchange's S&P/TSX composite index .GSPTSE was down 27.4 points, or 0.17%, at 16,496.07.