(Reuters) -U.S. stock index futures were lower on Tuesday after President Donald Trump's comments on potential pharma tariffs renewed worries of the impact of a trade war, while some downbeat corporate results also weighed on investor sentiment.

Late on Monday, Trump said he plans to announce pharma tariffs over the next two weeks, his latest on levies that have rattled global financial markets over the past months.

The news offset optimism stemming from his order that aimed to reduce the time taken for pharma manufacturing plant approvals. Drugmakers Eli Lilly and Pfizer were flat to slightly lower in premarket trading.

The latest development follows Trump's tariffs on foreign-made movies that were announced on Sunday. Wall Street closed lower on Monday, with the benchmark S&P 500 snapping a nine-session winning streak.

Ford Motor was the latest to suspend its annual outlook on Monday, joining a host of companies that shelved their forecasts in April. The automaker also flagged a hit of about $1.5 billion from the levies, sending its shares down 2.6% in premarket trading.

Tariff-driven uncertainty has led consumers, businesses and even the U.S. Federal Reserve to embrace a wait-and-watch mode as they struggle to gauge the impact of the levies and find ways to navigate them.

The Trump administration suggested last week that potential deals with trading partners were underway, but markets have seen no concrete results on that front.

The latest tariffs on the film and pharma industries are undermining the "likely misplaced" optimism that markets feel about the U.S. striking trade deals in the near future, said Marc Ostwald, chief economist, ADM Investor Services International.

At 05:30 a.m. ET, Dow E-minis were down 279 points, or 0.68%, S&P 500 E-minis were down 44.75 points, or 0.79%, and Nasdaq 100 E-minis were down 214.25 points, or 1.07%.

The Fed starts its 2-day meeting on Tuesday, with the central bank widely expected to stay put on interest rates. Comments from policymakers will be scrutinized for any clues that suggest their stance on monetary policy easing this year.

"We see little market-moving information emerging ... with a steady-as-she-goes payroll print for April, stable inflation numbers and prospects of engaging in trade deals, this should keep the Fed in wait-and-see mode for now," BNP Paribas analysts said.

Traders see about 79 basis points of policy easing by the end of 2025, with the first trim coming only in July, according to data compiled by LSEG.

Aircraft parts maker Transdigm, hotel operator Marriott and Marathon Petroleum are among the companies reporting before the bell.

Data analytics firm Palantir's shares were down 8.2% after the company's in line profit and modest revenue beat disappointed investors.

DoorDash was down 1% after the meal delivery firm said it will buy Deliveroo in a deal valuing the British rival at about 2.9 billion pounds ($3.86 billion).

($1 = 0.7505 pounds)