Updates at market close

By Nikhil Sharma and Fergal Smith

March 6 (Reuters) - Canada's main stock index fell on Thursday, weighed by declines for technology and financial shares, as the rapid pace of U.S. policy shifts on trade hurt investor sentiment globally.

The S&P/TSX composite index .GSPTSE ended down 286.78, or 1.2%, at 24,584.04, giving back nearly all of the previous day's rally.

U.S. benchmark, the S&P 500, posted even steeper declines, while the tech-heavy Nasdaq confirmed it was in a correction since December.

U.S. President Donald Trump exempted goods from both Canada and Mexico under a North American trade pact for a month from the 25% tariffs that he had imposed earlier this week, the latest twist in fast-shifting trade policy that has whipsawed financial markets and business leaders.

"The challenge is that no one can really anticipate or predict what Trump is going to do at any given point in time," said Shiraz Ahmed, senior portfolio manager and founder of Sartorial Wealth at Raymond James.

"The anxiousness is likely spilling over into the markets at the moment ... The market and everybody are just walking on egg shells and anticipating more bad than good."

Canada's trade surplus widened much more than expected to C$4 billion ($2.80 billion) in January as fears of U.S. tariffs pushed exports of cars and energy products higher.

The Toronto market's technology sector fell 3.3%, with shares of electronic equipment company Celestica Inc down 10.4%. The sector was trading roughly 14% below the all-time closing high it posted three weeks ago.

Heavily weighted financials fell 1.7%, while utilities ended 2% lower as bond yields climbed.

The materials group, which includes fertilizer companies and metal mining shares, was down 1.1% as the price of gold XAU= edged lower.

Shares of Aecon Group Inc ARE.TO tumbled 16.1% after the construction company fourth-quarter revenue expectations.

($1 = 1.4305 Canadian dollars)

(Reporting by Fergal Smith in Toronto and Nikhil Sharma in Bengaluru; Editing by Shreya Biswas and Alistair Bell)

((fergal.smith@thomsonreuters.com; +1 647 480 7446))