Stock futures were under pressure Thursday as investors sought out more clarity on the latest U.S. tariff measures.

Futures tied to the Dow Jones Industrial Average shed 378 points, or around 0.9%. S&P 500 futures and Nasdaq-100 futures lost 1.1% and 1.3%, respectively.

U.S. tariffs on Canadian, Mexican and Chinese imports took effect this week, rocking financial markets. Canada and China responded with retaliatory levies of its own, while Mexico said it would unveil measures over the weekend.

The major averages have lost more than 1% this week as trade tensions escalate. But the benchmarks got a boost Wednesday after the White House said it would grant a one-month delay for tariffs on automakers whose cars comply with the United States-Mexico-Canada Agreement.

This fueled traders’ hopes that Trump could provide further exemptions. Still, some on Wall Street expressed skepticism over the effectiveness of these exceptions.

“Exempting auto makers for just one month from draconian tariffs is like putting a Band-Aid on a bullet wound … given the torrent of trade/tariff announcements planned by the White House in the coming months,” Adam Crisafulli of Vital Knowledge wrote.

A continued unwind of the popular artificial intelligence trade that has boosted the market for more than a year also hurt Thursday’s premarket.

Notably, chipmaker Marvell Technology dropped more than 16% after the company issued mixed first-quarter guidance. Other semiconductor builders such as ON Semiconductor, Taiwan Semiconductor and Nvidia also slid before the bell.

On top of that, surveys of businesses this week including the Federal Reserve’s Beige Book and the Institute for Supply Management’s manufacturing reading indicated fear of rising input costs because of the tariffs, along with general rising uncertainty over Trump policies.