Aside from concerns over a tit-for-tat trade dispute between the U.S. and major economies including China, market focus has been mainly fixated by the economic crisis in Turkey.
Ankara's financial troubles have sparked fear of contagion with the country's currency having taken a deep slide. The lira has lost more than 45 percent of its value over the course of this year, according to Reuters.
Pressure has been ramped up in recent days, as market-watchers became jittery over Turkish President Recep Erdogan's control of the economy and Donald Trump saying last week that he supported doubling metal tariffs on the Middle Eastern country. Concerns appeared to have alleviated somewhat Tuesday, as the lira showed signs of rebounding.
U.S. import prices were surprisingly flat in July as a rally in the cost of fuels was offset by weak prices elsewhere, hinting that a strong greenback is tempering import inflation pressures.
The Labor Department said on Tuesday the unchanged reading in import prices last month followed an upwardly revised 0.1 percent drop in June. Economists polled by Reuters had forecast import prices gaining 0.1 percent in July.
In the year through the end of July, import prices rose 4.8 percent, their largest gain since February 2012.
Meantime, the U.S. Treasury is due to auction $26 billion in 52-week bills and $70 billion in four-week bills. No size announcements are due, however.