Wall Street closes mixed as trade concerns overshadow energy gains

Major equity indexes in the United States started the day on a positive note on the back of an improved sentiment that was also reflected upon rising European indices but struggled to preserve their momentum after President Trump threatened the EU by suggesting a possible 20% tariff on European car imports.

"Caution is very important among investors when it comes to trade ... this choppy, erratic and volatile action on a day-to-day and intraday basis is going to be the norm till things settle down," Andre Bakhos, managing director at New Vines Capital LLC in Bernardsville, New Jersey, told Reuters.

Meanwhile, a robust rally in energy shares helped the Dow Jones Industrial Average and the S&P 500 indexes hold on to their daily gains. At the first day of the OPEC summit in Vienna, producers decided to increase their output in order to bring the compliance back down to 100% from 146% and didn't provide any details on production allocations. Crude oil prices reacted positively and the barrel of West Texas Intermediate added more than $3 to settle at $68.58.

The S&P 500 Energy Index (SPNY) closed the day 2.2% higher to become the best performing sector of the day. 

After recording losses for the last eight sessions, the Dow Jones Industrial Average added 114.16 points, or 0.47%, to end the week at 24,575.86 points. The broader S&P 500 closed 4.28 points, or 0.16%, higher at 2,754.04 points. Finally, the tech-heavy Nasdaq Composite lost 23.69 points, or 0.31%, to 7,689.27. On a weekly basis, these three major indexes were down 2%, 0.9%, and 0.7% respectively.