U.S. stocks declined on Friday, with the Nasdaq Composite posting its first weekly drop in six, as concern escalated about Ukraine, two days before a vote in Crimea on joining Russia.
The CBOE Volatility Index (VIX), a measure of investor uncertainty, spiked nearly 9.3 percent to 17.73.
"The market is volatile, but not too volatile to cause any problems yet. The problem with yesterday was we had a lot of better economic news. I know there is concern about Ukraine and also China, but we had good numbers, yet couldn't maintain a rally," said Bruce Bruce Bittles, chief investment strategist at RW Baird.
"Maybe we're in a topping phase," he added.
U.S. Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov met in London Friday, and were unable to alleviate the situation. Russia had warned Ukraine's government had lost control of the nation, and the U.S. and the European Union said Russia would face sanctions if it does not back off from taking control of Crimea, where a referendum is scheduled for Sunday on whether to join Russia.
Kerry told a televised news conference that Russian President Vladimir Putin was not ready to "make any decision regarding Ukraine until after the referendum on Sunday."
A preliminary report from Thomson Reuters/University of Michigan had consumer sentiment at 79.9 in March versus an 82 estimate.
"The consumer is showing a lot of skepticism, even pessimism, about the economy. So here we have optimism in the stock market from investors but we don't have optimism from Main Street," said Bittles.
Separate economic data showed producer prices unexpectedly fell last month, with the 0.1 percent decline in the producer-price index coming after a 0.2 percent climb in January, the Labor Department said.