TORONTO -- Canada's main stock index closed down for a sixth straight day Thursday on losses in the energy sector amid sliding oil prices over ongoing uncertainty about trade talks.

"That's essentially due to the concern that global demand will slow because of the economic challenges in emerging markets and the ongoing trade disputes that are just happening between the U.S. and China, and the U.S. and other countries," said Anish Chopra, managing director with Portfolio Management Corp.

The October crude contract was down 95 cents at US$67.77 per barrel.

The S&P/TSX composite index closed down 36.63 points to 16,100.94, after reaching a low of 16,077.40 on 229.2 million shares traded.

Base metals, energy and information technology sectors closed down by as much as 2.3 per cent.

The cannabis-heavy health-care sector, materials and gold also ended the day in the red. Consumer staples had the largest gain, rising about one per cent on a 4.5 per cent increase in shares of Alimentation Couche-Tard after it posted strong quarterly results.

The Canadian dollar was essentially flat on the heels of comments from the Bank of Canada senior deputy governor Carolyn Wilkins about uncertain economic implications from tit-for-tat tariffs between Canada and the U.S. that has been a blow to business confidence.

It closed the session at 75.83 cents US, down from Wednesday's close of 75.84 cents US.

The loonie has bounced around depending on news coming out of Canada-U.S. trade talks, Chopra said in an interview.

"If the newsflow is modestly positive you get a bid on the Canadian dollar whereas if the newsflow is negative then the Canadian dollar loses ground."

Foreign Affairs Minister Chrystia Freeland wrapped up two hours of talks Thursday with her U.S. counterpart, which resulted in fresh marching orders for their respective negotiating teams.

In New York, the Dow Jones industrial average was up 20.88 points to 25,995.87. The S&P 500 index was down 10.55 points at 2,878.05, while the Nasdaq composite was down 72.45 points at 7,922.73

The October natural gas contract was down 2.3 cents at US$2.77 per mmBTU.

The December gold contract was up US$3 at US$1,204.30 an ounce and the December copper contract was up 2.65 cents at US$2.64 a pound.