Source: Sharecast
As of 1300 BST, Dow Jones futures were down 0.53%, while S&P 500 and Nasdaq-100 futures had the indices opening 0.65% and 0.92% lower, respectively.
The Dow closed 98.60 points lower on Monday, taking a small bite out of gains recorded in the previous session.
All eyes were firmly focused on the Federal Open Markets Committee on Tuesday, with investors hoping to gain more insight into the central bank's thinking at its first policy meeting since Donald Trump announced his "reciprocal" tariffs at the start of April. Fed funds futures suggest just a 2.7% chance of the central bank cutting rates.
Trade Nation's David Morrison said: "Traders appear to be taking profits and moving to the sidelines ahead of the Federal Reserve's FOMC meeting.
"Overall, US stock indices are pulling back from last week's highs. Traders look to be using the bounce since last month's tariff tantrum as an opportunity to reduce their market exposure. The question now is whether the indices consolidate at lower levels before another push higher, or if we can expect any rallies to be used as selling opportunities."
Also likely to draw some attention, Treasury Secretary Scott Bessent will testify before the House Appropriations Committee on Tuesday and could potentially provide insight into the "200 deals" that Trump claims to have struck with other countries.
On the macro front, March's goods and services trade balance figures will be published at 1500 BST.
In the corporate space, DoorDash, Advanced Micro Devices and Super Micro Computer will all report earnings on Tuesday.
Reporting by Iain Gilbert at Sharecast.com