U.S. stocks are set to open slightly lower Wednesday, after hitting four-year highs a day earlier.
U.S. stock futures slid into the red amid concerns about global growth.
Investors continue to keep an eye on Greece as Prime Minister Antonis Samaras meets with eurozone officials throughout the week. He is expected to push for a two-year extension of the country's bailout program, which would give the government more time to implement difficult reforms and help get the nation's economy back on track.
Analysts say markets will be looking for any comments out of Samaras' meetings for signs of further stimulus measures.
"We are unlikely to get any firm promises on the extension of deadlines or additional funding," said Elisabeth Afseth, fixed income analyst at Investec. "But it is more likely that we get supporting comments about 'great efforts made, difficult economic conditions', though with a warning more need to be done."
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Meanwhile in the U.S., investors will spend Wednesday parsing the minutes of the latest Federal Reserve meeting, while also digesting a report on existing home sales and the latest round of corporate earnings.
The Fed will release the minutes of its July meeting at 2 p.m. ET.
While the central bank didn't announce any further stimulus measures at its last meeting, investors will look for clues about whether a new round of quantitative easing could be coming when chairman Ben Bernanke speaks at the Jackson Hole, Wyo., symposium at the end of the month.
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U.S. stocks ended lower Tuesday, after the S&P 500 briefly rose above its highest closing level in four years.
World Markets: European stocks were all lower in afternoon trading. Britain's FTSE 100 fell 1.2%, the DAX in Germany slipped 0.9% and France's CAC 40 shed 0.9%.
Asian markets closed in the red. The Shanghai Composite lost 0.5%, the Hang Seng in Hong Kong fell 1.1%, and Japan's Nikkei edged lower 0.3%.
Economy: The National Association of Realtors will release data on existing home sales for the month of July at 10 a.m. ET. Sales are expected to come in at an annual rate of 4.55 million, up from June's 4.37 million, according to a survey of analysts by Briefing.com.
Companies: Toll Brothers (TOL), the luxury home builder, reported surprisingly strong earnings Wednesday morning, signaling further momentum in the U.S. housing market.
Express (EXPR) reported earnings of 18 cents a share, beating analyst expectations. But net sales, which increased to $454.9 million, were lower than analysts surveyed by Thomson Reuters had anticipated. Shares of the retailer were down nearly 2% in premarket trading.
Shares of Williams Sonoma (WSM)surged more than 10% after the houseware retailer reported better-than-expected second-quarter earnings and raised its forecast for the rest of the year.
American Eagle (AEGP) is expected to report earnings of 21 cents a share on $719 million in revenue, while Hewlett-Packard is expected to report earnings of 98 cents a share on $30.1 billion in revenue.
Dell (DELL) reported its quarterly results after the closing bell Tuesday. The company posted earnings that beat expectations, but shares fell 5% in premarket trading on disappointing guidance.
Hewlett-Packard (HPQ) will report after the closing bell.
Currencies and commodities: The dollar gained ground against the euro and the British pound, but fell against the Japanese yen.
Oil for September delivery fell 37 cents to $96.50 a barrel.
Gold futures for December delivery added $1.80 cents to $1,638.40 an ounce.
Bonds: The price on the benchmark 10-year U.S. Treasury edged higher, pushing the yield down to 1.80% from 1.81% late Tuesday.
