Updates at market close

By Rashika Singh and Fergal Smith

March 23 (Reuters) - Canada's main stock index rose on Monday by the most in five weeks, led by gains for technology and metal mining shares, as fears eased of a major escalation in the Middle East war.

The Toronto Stock Exchange's S&P/TSX composite index .GSPTSE ended up 566.40 points, or 1.8%, at 31,883.81, its biggest advance since February 13. On Friday, the index posted its lowest closing level in three months.

Iran denied that it had engaged in negotiations with the United States, after President Donald Trump postponed a threat to bomb Iran's power grid because of what he described as productive talks with unidentified Iranian officials.

"The broader market remains highly sensitive to shifting headlines around the Middle East conflict," said Allan Small, senior investment advisor at Allan Small Financial Group with iA Private Wealth. "Nobody knows what's going on as mixed signals from Washington and Tehran continue to whipsaw sentiment."

The technology sector <.SPTTTK> rose 3.4%, with shares of electronic equipment company Celestica Inc CLS.TO up 6.6%.

The materials group .GSPTTMT, which includes fertilizer companies and metal mining shares, added 3.2%. Copper HGc1 prices climbed but the price of gold XAU= was down 2.1%.

A crash between an Air Canada Express AC.TO jet and a fire truck at New York's LaGuardia injured dozens of passengers and led to hundreds of flight cancellations at the start of the working week, the latest disruption for airports and carriers that have been knocked off-kilter by a weeks-long budget standoff in Congress.

Still, shares of Air Canada rose 3.1%, helping to send the industrials sector .GSPTTIN 1.9% higher. Heavily weighted financials .SPTTFS were up 1.8%.

Just two of the 10 major sectors ended lower, including energy .SPTTEN. It lost 1.3% as the price of oil CLc1 settled 10.3% lower at $88.13 a barrel.