US equity futures were lower pre-bell Tuesday as traders monitored developments surrounding President Donald Trump's tariff policy.

Dow Jones Industrial Average futures slipped 0.6%, S&P 500 futures fell 0.5%, and Nasdaq futures were down 0.5%.

The White House is expected to unveil an extensive reciprocal tariff policy on Wednesday.

Oil prices slipped, with front-month global benchmark North Sea Brent crude down 0.1% at $74.66 per barrel and US West Texas Intermediate crude also 0.1% lower at $71.40 per barrel.

The Purchasing Managers' Manufacturing index, scheduled for release at 9:45 am ET, is seen at 49.8 in March versus 52.7 in February, according to estimates compiled by Bloomberg.

The Institute for Supply Management Manufacturing index, due at 10 am ET, is expected at 49.5 in March versus 50.3 previously. Construction spending is expected to have risen by 0.3% in February, following a 0.2% downtick in January. Forecasters see job openings based on the Labor Department's Job Openings and Labor Turnover Survey coming in at 7.69 million for February compared with January's 7.74 million.