June 3 (Reuters) - Canada's main stock index opened

lower on Tuesday, led by losses in metal miners' shares, as

investors awaited possible trade negotiations between the U.S.

and its trading partners for more clarity on the tariff war and

economic uncertainty.

At 9:31 a.m. ET (1331 GMT), the Toronto Stock Exchange's

S&P/TSX composite index was down 0.13% at 26,353.48

points.