(Reuters) -U.S. stock index futures dropped on Wednesday as investors awaited details of U.S. President Donald Trump's tariff plans to assess their impact on the global economy, corporate earnings and financial markets.

Wall Street's main indexes have been volatile in recent days, with investors preferring to hold safer assets such as gold and government bonds over risky equities, as they about the extent of economic damage from the U.S.-led tariff war.

Details of Trump's "Liberation Day" tariff plans were still being formulated and closely held ahead of a White House Rose Garden announcement ceremony scheduled for 4 p.m. ET (2000 GMT).

Futures extended losses after a Bloomberg report said China has taken measures to limit its companies from making investments in the U.S. in an effort to gain more leverage in potential trade talks with the Trump administration. 

Trump said that his reciprocal tariff plans aim to equalize the comparatively lower U.S. tariff rates with those imposed by other nations. However, the structure of these duties remains ambiguous amidst reports suggesting Trump might be contemplating a universal tariff of 20%.

"Perhaps the most important question is whether this announcement will tip the scales towards a global recession," said Oliver Blackbourn, portfolio manager at Janus Henderson Investors.

"While we believe this is unlikely at present, it is important to acknowledge that U.S. equities are relatively expensive, which could make them more vulnerable to any negative surprises."

By 6:55 a.m. ET, U.S. S&P 500 E-minis were down 27.5 points, or 0.48%, Nasdaq 100 E-minis were down 119.75 points, or 0.61%, Dow E-minis were down 178 points, or 0.42%.

Futures tracking the domestically focused Russell 2000 index were down 0.6%.

Tech stocks, which have been at the forefront of the selloff this week, slipped in premarket trading. Nvidia slid 1.4%, Microsoft slipped 0.6%, while Amazon.com dropped 1.1%.  

U.S. stocks have come under sharp selling pressure this year, with the benchmark S&P 500 and tech-heavy Nasdaq falling 10% from their record highs last month and confirming a correction.

The S&P 500 shed 4.6% in the first quarter, its biggest three-month decline since July 2022.

March U.S. private payrolls and factory orders data are scheduled for release later in the day. However, focus is on the crucial monthly non-farm payrolls data as well as Fed Chair Jerome Powell's speech on Friday for insights on the health of the U.S. economy and trajectory of interest rates.

Traders are betting on three rate cuts from the Fed this year but the prospect of tariff-induced inflationary pressures has clouded the outlook.

Among stocks, Tesla dipped 2.4% ahead of its first-quarter deliveries numbers. The stock has fallen 33.5% so far this year.

(Reporting by Sruthi Shankar and Pranav Kashyap in Bengaluru; Editing by Anil D'Silva)