U.S. stock index futures slipped on Wednesday after a sharp rally in the previous session, when easing tariff tensions boosted sentiment, as investors focused on AI bellwether Nvidia's upcoming earnings and developments on the trade front.

US stock futures are slightly up ahead of Nvidia Corp.’s earnings as investors waited to gauge the impact of the trade war and outlook for artificial intelligence.

Nvidia is forecast to post earnings per share of $0.893 on revenue of $43.12 billion for the three months to April 31, both up substantially from last year, Investing.com data showed.