The energy group retreated 1 percent as oil prices slipped on an increased focus on U.S. production increases. U.S. crude oil futures settled 61 cents lower at $53.17 a barrel. [O/R]

Energy stocks got a boost on Tuesday from revived prospects for the Keystone XL pipeline. But on Monday the group had hit a nearly two-month low amid investor worries about a potential U.S. border adjustment tax.

"Prime Minister (Justin) Trudeau has to play his cards pretty carefully here. The last thing you want is have some sort of taxation on oil going into the U.S," said Ian Nakamoto, equity specialist at MacDougall, MacDougall & MacTier, a division of Raymond James.

TransCanada Corp fell 1.3 percent to C$62.71 as the country's energy regulator said it would restart from the beginning a hearing into the company's proposed Energy East pipeline.

Fellow pipeline operator Enbridge Inc declined 2.7 percent to C$56.55 after announcing it would pay about $170 million to take private Midcoast Energy Partners LP.

The Toronto Stock Exchange's S&P/TSX composite index closed down 39.71 points, or 0.25 percent, at 15,575.81.

The index had moved intraday on Wednesday within 11 points of its all-time high at 15,685.13, but has since drifted lower.

"We are going to have a bit of a vacuum in terms of news, so we might have a bit of a pause, or a slight correction here," Nakamoto said.

Five of the index's 10 main groups ended lower, with the heavyweight financials group dipping 0.2 percent.

For the week, the index gained 0.2 percent.

Celestica surged 11.4 percent to C$18.60 after its adjusted earnings beat expectations and it said it would exit the oversupplied solar panel manufacturing market.

Rogers Communications Inc extended a rally to its highest level since August as investors cheered Thursday's results that suggested its turnaround was on track. It advanced 1.3 percent to C$56.77.

Restaurant Brands International Inc advanced 1.7 percent to C$65.72. The company said it would expand its coffee and doughnut chain, Tim Hortons, into Mexico.

The materials group, which includes precious and base metals miners and fertilizer companies, rose 0.2 percent as gold prices steadied and gold stocks gained. [GOL/]

Gold futures dipped 0.1 percent to $1,188.30 an ounce.

(Additional reporting by Alastair Sharp; Editing by Paul Simao and Lisa Shumaker)

By Fergal Smith