U.S. stock benchmarks closed mostly lower on Wednesday, with technology shares weighing down the market.

The S&P 500 index shed 1.56 points, or 0.1%, to 2000.72, and the Nasdaq Composite Index dropped 25.62 points, or 0.6%, to 4572.57. The Dow Jones Industrial Average eked out gains, rising 10.72 points, or 0.1%, to 17078.28.

Stocks had initially advanced, as reports of easing tensions in Ukraine helped spark a rally in Europe and early U.S. gains. But shares of Apple Inc. led the tech sector lower and weighed on broader benchmarks through the rest of the day. The tech sector of the S&P 500 closed with a 0.7% loss.

Apple had the second-steepest losses in the index, down 4.2%. The declines came one week before it is expected to unveil its latest iPhone, and as competitor Samsung launched a new product. Andy Hargreaves, analyst with Pacific Crest, warned that he might downgrade Apple's stock unless next week's event includes massive opportunities for profit.

"Investors really want to play it safe coming into something like that," said Jonathan Corpina, senior managing partner at Meridian Equity Partners. "Then the rest of the sector gets pulled down, too."

The company's stock traded at a blistering pace, with more than 120 million shares changing hands, well above its long-term average of 68.66 million shares per session. Before Wednesday, Apple had rallied 38% since announcing a stock split and better-than-expected earnings in late April.

Delta Air Lines had the steepest losses in the S&P 500, falling 5.2% after it warned about its third-quarter fuel costs. The stock had also rallied in recent sessions and was up 49% year-to-date before Wednesday's decline.

"These are crowded trades that people are trying to exit," said Michael Antonelli, sales trader at Robert W. Baird. "And in crowded trades, the reactions can be steep."

European markets rallied as Russian President Vladimir Putin confirmed that he and Ukrainian President Petro Poroshenko had agreed to the outlines of a cease-fire between Ukrainian forces and pro-Russian rebels fighting in eastern Ukraine. The Stoxx Europe 600 Index gained 0.6%. Germany's DAX Index rose 1.3%.

The Ukraine conflict "definitely has been a drag on the European economy, and Europe is a big part of the global economy," said Paul Zemsky, who oversees $30 billion as chief investment officer of multi-asset strategies at Voya Investment Management. "If that gets cleared up, the market can go higher."

Investors like Mr. Zemsky are now looking ahead to Thursday's statement from the European Central Bank. "It's a big, big meeting," he said. Recent statements from ECB President Mario Draghi have boosted investor hopes that the central bank would take steps to stimulate the region's economy, Mr. Zemsky said, so "if he doesn't come up with something, people will just throw up their hands and dismiss Europe as an asset class for a while."

His fund has been making incremental additions to its holdings of European stocks, as a bet that the conflict in Ukraine won't cause lasting damage to the region's economy. But he remains downbeat on the prospect of gains in the region, particularly compared with the U.S.

U.S. stocks have advanced in recent weeks, as investors say improving economic data and low interest rates in the U.S. have helped make them an attractive area for investment. The S&P 500 closed Wednesday just 0.1% below its all-time high. The Dow isn't far behind, off 0.3% from its July 16 record close.

"When you get rid of this day-to-day noise, you're looking at a pretty decent outlook for global growth," said Geoffrey Pazzanese, who manages $600 million in international stocks for Federated Investors. He still expects growth in the U.S. to be stronger than other economies, so his fund has been buying shares of companies that export products, such as German car makers.

A report on factory orders in July showed a 10.5% increase, nearly in line with the 11% increase expected by economists surveyed by The Wall Street Journal. And the Federal Reserve's latest survey of regional business conditions showed that economic activity picked up during the summer

Asian stocks finished mostly higher, boosted by positive Chinese data. The HSBC China services purchasing managers index for August rose to a 17-month high.

U.S. Treasury prices rose, sending the yield on the benchmark 10-year note down to 2.409%.

In other corporate news, Netflix has reached an agreement with Time Warner's Warner Bros. to secure streaming rights for the TV show "Gotham, " marking the latest major content acquisition by Netflix, The Wall Street Journal reported. Netflix shares rose 0.2%, and shares of Time Warner edged up less than 0.1%.

In commodity markets, crude-oil futures rose 2.9% to $95.54 a barrel. Gold futures gained 0.4% to $1,268.90 an ounce.