Wall Street declined as US retail sales grew less than expected while oil prices jumped amid concern that escalating violence in Iraq might threaten to destabilise the country and disrupt oil supplies.
Retail sales rose 0.3 percent in May, well below expectations for a 0.6 percent advance. To be sure, sales for April were upwardly revised to a 0.5 percent increase.
"We're not getting the big acceleration that many people hoped for," Michelle Girard, chief US economist at RBS Securities in Stamford, Connecticut, told Bloomberg News.
Separately, initial claims for state unemployment benefits rose 4,000 to a seasonally adjusted 317,000 for the week ended June 7.
In the final hour of trading in New York, the Dow Jones Industrial Average fell 0.67 percent, the Standard & Poor's 500 Index shed 0.72 percent, while the Nasdaq Composite Index declined 0.86 percent.
Earlier this week, the World Bank lowered its forecast for US economic growth this year to 2.1 percent this year, from a previous 2.8 percent.
Slides in shares of Home Depot, down 2 percent, and those of Caterpillar, down 1.9 percent, led the Dow lower.
Shares of Lululemon plunged, last 15.3 percent weaker, after the company downgraded its profit and revenue outlook for the year.
"2014 is very much a transitional year for Lululemon, and we are on track with the improvements we have set out to achieve," Laurent Potdevin, Lululemon's CEO, said in a statement. "We are focused on building a scalable foundation to further elevate our North American business and pursue the brand's incredible international potential."
Analysts were not so sure.
"The second quarter guidance is for a real deceleration from the already anaemic first quarter," Cowen and Co analyst Faye Landes told Reuters
In Europe, the Stoxx 600 Index inched higher to end the session at 347.83. Germany's DAX fell 0.1 percent, while France's CAC 40 dipped 0.02 percent. The UK's FTSE 100 rose 0.06 percent.
The price of oil jumped amid concern about a return to civil war in Iraq and a disruption of supplies from OPEC's No. 2 oil producer. Islamist rebels have overrun several key cities in the north of Iraq and are threatening to take their fight to Baghdad.
"Iraq had been a bright spot ramping up production and now we're in the midst of a very ugly conflict," John Kilduff, a partner at Again Capital, a New York-based hedge fund that focuses on energy, told Bloomberg News. "Most of the production is in the south but if the rebel advance continues this could be threatened."
West Texas Intermediate jumped as much as 2 percent while Brent gained 2.2 percent. The Thomson Reuters/Jefferies CRB index climbed 1.1 percent, the most in two months.
"Oil spiking isn't a problem right now, since this is strictly a geopolitical response, but if it stays substantially above US$115 for a week or two, that's when it will become an issue for consumer spending or the economy at large," Paul Schatz, chief investment officer at Heritage Capital in Woodbridge, Connecticut, told Reuters.
The months of June through August are key driving ones in the US as they coincide with school holidays.