U.S. stock index futures pointed to a lower open on Tuesday as traders eyed escalating geopolitical tensions concerning North Korea while earnings season kicked into full gear.
U.S. Vice President Mike Pence reassured Japan of American commitment to reining in North Korea's nuclear and missile ambitions on Tuesday, after warning that U.S. strikes in Syria and Afghanistan showed the strength of its resolve.
Pence arrived in Tokyo from South Korea, where he assured leaders of an "iron-clad" alliance with the United States in the face of the reclusive North, which has conducted a series of missile and nuclear tests in defiance of U.N. sanctions.
Investors also kept an eye on France, as campaigning ramped up ahead of the first round of the presidential election. Left-wing candidate Jean-Luc Melenchon's surge in polls added to investors' worries as it becomes unclear who will win the contest.
On the data front, housing starts fell 6.8 percent in March, more than the expected 3.9 percent drop. Industrial production for March data
On the earnings front, Bank of America, Johnson & Johnson and UnitedHealth reported before the bell. IBM, Intuitive Surgical and Yahoo are all due to report after the market close.
Goldman Sachs also reported first-quarter results, disappointing Wall Street analysts. The banking giant's stock fell about 2.5 percent in the premarket, pressuring Dow
In Europe, the pan-European Stoxx-600 index was around 0.89 percent lower on Tuesday after UK Prime Minister Theresa May "reluctantly" called for an early election. In Asia, the Shanghai Composite in China closed 0.79 percent lower, while the Nikkei in Japan closed 0.35 percent higher.
In oil markets, prices slipped on Tuesday after a U.S. government report suggested increased production levels.
Brent crude traded at around $54.95 a barrel on Tuesday, down 0.74 percent, while U.S. crude was around $52.32 a barrel, down 0.63 percent.
—Reuters contributed to this report.