March 6 (Reuters) - Canada's main stock index finished flat on Tuesday as gains in gold producers were offset by weakness in energy shares and as global equities markets were supported by signs North Korea is willing to hold talks with the UnitedStates.
* The Toronto Stock Exchange's S&P/TSX composite index .GSPTSE ended up 3.91 points, or 0.03 percent, at 15,545.19.
* South Korea said the North will also suspend nuclear testswhile talks with the United States are underway. The prospect of talks after months of tensions betweenNorth Korea and the United States helped put a floor underglobal markets, as did a push from U.S. Republican lawmakers toget U.S. President Donald Trump to pull back from proposedtariffs on steel and aluminum. MKTS/GLOB Gold producers .SPTTGD climbed 1.1 percent, helping tosupport the larger materials sector as gold prices firmed on thepotential progress with North Korea. GOL/
* Goldcorp G.TO advanced 2.7 percent to C$17.01, whileTeck Resources TECKb.TO was up 1.1 percent at C$36.68 as goldfutures GCc1 rose 1.2 percent to $1,333.4 an ounce.
* But the market was capped by the heavyweight energy group .GPTTEN , down 0.5 percent. Canadian Natural Resources CNQ.TO fell 1.1 percent to C$39.82, while Suncor Energy SU.TO was off0.2 percent to C$41.40.
* Canadian National Railway CNR.TO was the biggest drag onthe index, down 2.0 percent at C$95.24 as CIBC cut its targetprice to C$108 from C$111 the day after the rail company's chiefexecutive officer abruptly stepped down. Bombardier Inc BBDb.TO fell 5.8 percent to C$3.77 afterit said it will sell equity to strengthen its balance sheet aspart of a five-year turnaround plan. Canopy Growth WEED.TO was among the most heavily tradedshares, up 1.7 percent at C$32.93 after Bloomberg reported thatthe cannabis producer had bid for Spanish firm Alcaliber SA. The TSX posted eight new 52-week highs and four new lows.Across all Canadian issues there were 25 new 52-week highs and16 new lows. Volume on the TSX index was 220.90 million shares.