U.S. stocks were tipped to open flat to slightly lower Monday, with focus turning to this week's closely-anticipated U.S. Federal Reserve meeting.
There were mixed cues from global markets, with European shares opening the day higher while Asian stock markets closed mostly lower following weak data from China at the weekend.
U.S. stock futures fluctuated between slight gains and losses, with Dow Jones industrial average futures last trading about 20 points lower.
The U.S. central bank meets on Wednesday and Thursday amid continued debate over the timing of the first interest rate hike in almost a decade.
Futures markets are pricing in about a 24 percent chance of a rate hike this week following recent volatility in markets, heightened concerns about the outlook for China's economy and low inflation expectations.
"Our Fed-watcher Philip Marey maintains his long-held view that December is the most likely date for the Fed's policy rate lift-off," analysts at Rabobank said in a note. "Fasten your seatbelts, as it could be another volatile week ahead of us."
This week's Fed meeting was expected to overshadow concerns about China for now. Data on Sunday showed investment and factory output in China fell short of analyst expectations in August, fueling concerns about the outlook for the world's second biggest economy.
China's factory output rose 6.1 percent from a year earlier, compared with market expectations for a 6.4 percent rise.
Chinese officials said on Monday that Beijing will work to reform large state-owned companies, but the news failed to shore up shares with the benchmark Shanghai Composite index closing down 2.67 percent.
There are no major U.S. economic releases on the calendar for Monday, with this week's key data including retail sales and industrial output numbers for August on Tuesday.
U.S. stocks closed mildly higher on Friday, with the Dow Jones industrial average closing 0.6 percent higher.
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Elsewhere, oil prices dipped with U.S. crude futures down 0.5 percent at $44.40 a barrel, while the U.S. dollar was little changed against the euro and the .