The S&P 500 was down 4.12 points, or 0.14 percent, to 2,853.58.
The Russell 2000 index of smaller-company stocks fell 4.08 points, or 0.2 per cent, to 1,686.80.
The Turkish lira briefly dropped almost 20 percent against the dollar after US President Donald Trump tweeted that he has authorized the doubling of tariffs on steel and aluminum imports from Turkey.More news: Sunil Gavaskar declines invitation for Imran Khan's oath-taking ceremony
On the TSX 78 issues advanced and 162 declined as a 0.5-to-1 ratio favoured decliners. Tech stocks have been at the center of a sharp recovery in the S&P since a market rout in February, driving the index close to its record high.
Microchip's shares fell 10.5 percent, the biggest decliner on the S&P, after it forecast disappointing second-quarter revenue.
Shares of Apple rose 1 percent, while those of Amazon were up 0.5 percent and Microsoft 0.3 percent.
The Nasdaq added 27.09 points, or 0.3 percent.More news: Anti-racist protesters in Charlottesville angered by heightened police presence, riot gear
For the week, the Dow fell 0.6 per cent and the S&P 500 dipped 0.3 per cent.
Rite Aid (RAD.N) fell 11.5 percent after the drug store chain and USA grocer Albertsons Cos ABS.N agreed to terminate their merger agreement.
China's tit-for-tat response to the Trump administration's latest round of tariffs dragged down shares of trade-sensitive stocks such as Caterpillar and Boeing.
Declining issues outnumbered advancing ones on the NYSE by a 1.04-to-1 ratio; on Nasdaq, a 1.10-to-1 ratio favored advancers. The Nasdaq Composite also pulled back 0.7 percent to 7,839.11 and snapped an eight-day winning streak. That compares with the 6.4 billion-share daily average for the past 20 trading days, according to Thomson Reuters data.More news: Gerard Pique: Barcelona and Spain confirms global retirement
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