(Reuters) -U.S. stock index futures eased on Thursday, a day after markets were supported by Nvidia's fleeting $4 trillion milestone, while investors shifted their focus to upcoming economic data and pivotal trade talks.

At 5:30 a.m. ET, Dow E-minis were down 107 points, or 0.24%, U.S. S&P 500 E-minis were down 11.75 points, or 0.19%, and Nasdaq 100 E-minis were down 38 points, or 0.16%.

President Donald Trump announced on Wednesday a new 50% tariff on copper to start on August 1 and threatened a 50% tariff on exports to the U.S. from Brazil. He also issued tariff notices to seven minor trading partners.

U.S-listed shares of Brazilian firms fell in premarket trading, with Petrobras and Itau Unibanco down 1.3% each. Banco Santander lost 2.1%.

Yet, several countries are still waiting for official word from the White House, as investors keep a close eye on the evolving trade negotiations.

Hopes are also high for a breakthrough with India, with both Trump and top officials hinting a deal is within reach, while talks with the European Union inch closer to a framework agreement.

Wall Street closed higher on Wednesday, with the tech-heavy Nasdaq notching a record close - propelled by Nvidia's historic leap to a $4 trillion valuation, making it the first company ever to hit that mark.

The chip giant's shares continued to climb, up 0.4% in premarket trading.

The S&P 500 and the Dow also eked out gains, buoyed by the minutes from the Federal Reserve's June meeting that showed most officials said they expect rate cuts will be appropriate later this year, with price shocks from Trump's import taxes expected to be "temporary or modest."

While a July Fed rate cut seems off the table, the odds of a September reduction rose to about 70% after the minutes' release, up from around 60%, according to CME Group's FedWatch tool.

"The resilient U.S. economic backdrop gives the Fed time to study the effects of tariff increases on prices and growth before resuming interest-rate reductions," said Elias Haddad, senior markets strategist at Brown Brothers Harriman.

Last week's robust labor market report sent Wall Street's major indexes to fresh record highs, signaling a rebound from April's sharp sell-off following "Liberation Day" tariff announcements.

Now, the blue-chip Dow is 1.4% away from reclaiming its December 4 all-time high.

Investors will parse through a reading of initial jobless claims figures for the week of July 5, due at 8:30 a.m. ET, for the next pulse check on the labor market.

Among stocks, WK Kellogg leapt 50.1% following reports that Italian candy maker Ferrero was nearing a deal to buy the cereal maker.