At 11:11 a.m. ET, the Toronto Stock Exchange's S&P/TSX composite index was little changed, edging 1.88 points lower, to 15,620.69, reversing gains earlier in the morning session.
Recent military and geopolitical events have also taken a toll on the markets, he added, pointing to US air strikes in Afghanistan and Syria, as well as increased tensions with North Korea. Some disappointing quarterly results and uncertainty over fiscal promises by U.S. President Donald Trump added to pressure on Wall Street. Seven of its 10 main groups were lower, although advancers and decliners were equally matched overall. "The reflation trades in the USA are spilling over into Canada", said Noman Ali, senior portfolio manager at Manulife Asset Management.
In commodities news, the May crude oil contract lost 24 cents to US$52.41 per barrel, while the more heavily traded June crude contract declined 26 cents at US$52.85 per barrel. "If inflation expectations are coming down, that's not good for cyclicals generally", said Ali.
Energy stocks climbed 0.3 per cent after slipping 0.9 per cent in the previous session.
WTI light sweet crude oil was down 37 cents at $52.28 a barrel amid signs that USA production continues to surge.
Financials, which account for just over a third of the index's weight, slipped 0.5 percent.
Offsetting the advances was a 0.9 per cent decline by the materials group, home to precious and base metals miners and fertilizer companies.
Canadian government bond prices were higher across a flatter maturity curve, with the two-year price up 3.5 Canadian cents to yield 0.712 per cent and the benchmark 10-year rising 33 Canadian cents to yield 1.478 per cent.
Rogers Communication Inc rose 1.1 percent to C$62.08 after the country's largest wireless company by market share reported a sharp rise in first-quarter profit and higher revenue after markets closed on Tuesday.