U.S. stocks looked set to open lower on Monday as rising geopolitical tensions in Asia and President Donald Trump's accusation that his predecessor Barack Obama wiretapped him weighed on investors' risk appetite.
Some investors worried that the latest development could distract Trump from his economic agenda of introducing tax cuts and simplifying regulations, which have powered the financial market higher since the election.
The S&P 500 and the Nasdaq have risen for six straight weeks, extending a post-election rally that started in November.
However, the lack of detail on Trump's proposals and political tensions surrounding his relationship with Russia have raised concerns.
Investors are focusing more on politics and have become more selective in what they buy, the Bank for International Settlements said on Monday.
"The market is susceptible to short-term swings and choppy behavior predicated on something Trump says," said Andre Bakhos, managing director at Janlyn Capital in Bernardsville, New Jersey.
"Most investors are positive about the Trump administration, however, there is caution that something could be said by the administration that could derail the enthusiasm."
Rising geopolitical tensions in East Asia also weighed after North Korea fired four ballistic missiles.
Dow e-minis were down 44 points, or 0.21 %, with 31,722 contracts changing hands at 8:39 a.m. ET (1339 GMT)
S&P 500 e-minis were down 7.25 points, or 0.3 %, with 181,774 contracts traded.
Nasdaq 100 e-minis were down 14.25 points, or 0.27 %, on volume of 29,525 contracts.
Investors are wary of inflated market valuations. The S&P is trading at about 18 times forward earnings estimates against the long-term average of 15 times, according to Thomson Reuters data.
A flurry of economic data, culminating with Friday's nonfarm payrolls report, will demonstrate the strength of the U.S. economy this week.
A Commerce Department report on Monday is expected to show factory goods orders increased 1 % in January after a 1.3 % rise in December. The data is due at 10:00 a.m. ET (1500 GMT).
Among stocks, General Motors fell 1.7 % to $37.58 in premarket trading after the automaker said it would sell its European Opel and Vauxhall operations to France's PSA Group. Netflix rose 1.44 % to $141.08 after UBS upgraded the stock to "buy" from "neutral".
Tyson Foods was down 2.5 % at $61.65 after a strain of bird flu was detected in a chicken breeder flock on a Tennessee farm contracted with the company.