07:35 AM EDT, 06/02/2025 (MT Newswires) -- US benchmark equity indexes were trending lower before Monday's opening bell as investors weigh renewed tensions between the US and China over tariffs.

The S&P 500 slipped 0.5% in premarket activity, the Dow Jones Industrial Average decreased 0.4%, while the Nasdaq was off 0.6%. The indexes finished the previous trading session mixed, with the Nasdaq and the S&P 500 posting their biggest monthly gains in May since November 2023.

China's Ministry of Commerce on Monday said the US violated the trade truce reached between the two countries in Switzerland and vowed to protect its interests.

"If the US insists on its own way and continues to damage China's interests, China will continue to take resolute and forceful measures to safeguard its legitimate rights and interests," the statement read, according to a translation.

Last month, the US and China agreed to suspend most tariffs on each other's imports for 90 days. However, US President Donald Trump on Friday accused China of violating the pact. "China, perhaps not surprisingly to some, has totally violated its agreement with us," he said in a social media post.

The latest escalation between the US and China comes amid judicial developments surrounding Trump's tariffs. On Thursday, a federal appeals court granted the Trump administration's request to temporarily pause a ruling that struck down a series of tariffs announced by the White House. The US Court of International Trade on Wednesday ruled that Trump overstepped his authority by imposing duties under the International Emergency Economic Powers Act.

US Treasury yields moved slightly higher in premarket action, with the two-year rate rising 0.4 basis point to 3.92% and the 10-year rate inching up 2.2 basis points to 4.4%.

Monday's economic calendar has the final Purchasing Managers' Manufacturing Index for May at 9:45 am ET, followed by the Institute for Supply Management's manufacturing index for the same month and the construction spending report for April at 10 am.

Federal Reserve Bank of Dallas President Lorie Logan is scheduled to speak at 10:15 am, while Chicago Fed President Austan Goolsbee speaks at 12:45 pm.

Shares of Moderna ( MRNA ) rose 5.5% premarket as the company said the US Food and Drug Administration approved its new COVID-19 vaccine. Cleveland-Cliffs (CLF) skyrocketed 32%, Steel Dynamics (STLD) gained 13%, while Nucor (NUE) was up 14% as Trump reportedly said on Friday that he planned to increase duties on imported steel and aluminum to 50% from 25%.

Ulta Beauty (ULTA) rose 11% following its better-than-expected quarterly results last week. Tesla (TSLA) fell 1.9%, while Palantir (PLTR) was down 1.5%.

Campbell's (CPB) and Science Applications International (SAIC) are scheduled to release their latest quarterly results before the bell.

West Texas Intermediate crude oil rose 3.6% to about $63 a barrel before the open. The Organization of the Petroleum Exporting Countries and its allies, or OPEC+, on Saturday decided to raise output by 411,000 barrels per day in July.

Gold increased 1.7% to $3,370 per troy ounce, while bitcoin dipped 0.7% to $104,371.