June 4 (Reuters) - Canada's main stock index opened lower on Tuesday, dragged by losses in energy and materials shares as oil and copper prices fell, while investors await the Bank of Canada's interest rate decision on June 5.
At 9:30 a.m. ET (13:30 GMT), the Toronto Stock Exchange's S&P/TSX composite index (.GSPTSE), opens new tab was down 121.64 points, or 0.55%, at 21,995.05.
Reporting by Shubham Batra in Bengaluru