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TSX ends down 1.6% at 24,759.15

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Posts biggest decline since March 4

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Technology sector falls 3%

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Aya Gold & Silver ( AYASF ) tumbles 15.8%

(Updates at market close)

By Fergal Smith

March 28 (Reuters) - Canada's main stock index fell on

Friday by the most in three weeks as U.S. data and an expanding

trade war raised fears of a global economic slowdown.

Toronto Stock Exchange's S&P/TSX composite index

ended down 401.91 points, or 1.6%, at 24,759.15, its lowest

closing level since March 18 and its biggest decline since March

4. For the week, the index was down 0.8%.

Major U.S. benchmark, the S&P 500, posted an even steeper

decline.

"When the president of the United States tries to shut down

the global economy it can be problematic for stock markets,"

said Matt Skipp, president of SW8 Asset Management. "How can any

business leader make an impactful decision, whether it's

purchasing for their businesses, when the government changes its

mind every day."

U.S. consumer spending rebounded less than expected in

February while a measure of underlying prices increased by the

most in 13 months, stoking fears the economy was facing a period

of tepid growth and high inflation amid an escalation in trade

tensions.

Canadian GDP rose 0.4% in January but a preliminary estimate

showed activity flatlining in February.

U.S. President Donald Trump and Prime Minister Mark Carney had a

conversation that both men described as productive, although the

Canadian leader said Ottawa would be imposing retaliatory

tariffs next week as promised.

On Wednesday, Trump announced a 25% tax on imported

vehicles. Autos are Canada's second-largest export.

The technology sector was the biggest decliner, falling 3%,

with e-commerce company Shopify Inc ( SHOP ) ending 5.7% lower.

The materials group, which includes metal mining shares,

fell 1.7%. It was weighed down by a 15.8% drop in the shares of

Aya Gold & Silver Inc ( AYASF ) after the company reported

quarterly results.

Consumer discretionary fell 2.2%, with auto parts suppliers

adding to their recent declines and shares of Restaurant Brand

International losing 6.1%.

Industrials were down 2.2% as railroad shares declined and

heavily weighted financials ended 1.6% lower.