Photo: The Canadian Press. All rights reserved.

The former Toronto Stock Exchange home in Toronto, August 18 2011. THE CANADIAN PRESS/Aaron Vincent Elkaim

The Toronto stock market headed for a sharply lower open Thursday amid growing worries about a slowing global economy.

Resource stocks will lead declines as commodity prices gave up ground after the U.S. Federal Reserve signaled conditions don't warrant another round of economic stimulus right now. And traders were braced for more data from China showing the world's second-largest economy slowing faster than thought.

Sliding prices for oil and copper helped push the Canadian dollar down 0.37 of a cent to 97.68 cents US.

U.S. futures also signaled selling pressure at the open as the Dow Jones industrial futures lost 87 points to 12,449, the Nasdaq futures were down 14.5 points to 2,547 and the S&P 500 index futures dropped 10.3 points to 1,326.

Demand worries pushed the August crude contract on the New York Mercantile Exchange down $1.23 to US$84.58 a barrel.

Crude has plummeted from $106 in May amid expectations that a global slowdown led by Europe, the U.S. and China will undermine oil demand.

Copper prices slid five cents to US$3.39 a pound while bullion gave back $12.70 to US$1,563 an ounce.

There had been hopes that the minutes of the most recent Federal Reserve meeting would indicate the Fed may engage in a third round of securities purchases aimed at increasing the supply of money in the economy, so-called quantitative easing.

Market-watchers concluded that meant no likely action at the Fed's next meeting July 31-Aug. 1.

There was also a degree of suspense a day before the release of the latest Chinese economic growth data.

Data are expected to show growth in the three months ending in June fell as low as 7.3 per cent, down from the previous quarter's nearly three-year low of 8.1 per cent. That is in line with this year's official 7.5 per cent target. But revenues for companies in construction, shipbuilding and export manufacturing are down by up to half compared with a year ago.