U.S. stock index futures were down on Tuesday, pulling back after a sharp rally fueled by a U.S.-China trade truce, as investors turned their focus to a key U.S. inflation reading that could shape the outlook for monetary policy.

U.S. equity futures nudged lower in early Tuesday trading as investors hit pause on one of the strongest rallies of the year heading into a key inflation reading prior to the opening bell. Stocks ended firmly higher on Monday,