US equity futures fell ahead of Friday's opening bell as traders monitored US-Iran negotiations over nuclear policy and President Donald Trump's latest tariff threats.

Dow Jones Industrial Average futures were down 1.2%, S&P 500 futures were declining 1.3%, and Nasdaq futures were 1.7% lower.

US and Iranian negotiators are expected to resume talks in Rome on Friday on Tehran's nuclear program.

On trade, Trump moved to raise tensions again early Friday, threatening to slap Apple (AAPL) with a tariff of at least 25% on foreign-made iPhones and recommending a 50% tariff on the European Union, starting on June 1.

Oil prices were lower, with front-month global benchmark North Sea Brent crude down 1.2% at $63.70 per barrel and US West Texas Intermediate crude 1.2% lower at $60.46 per barrel.

The new home sales report, slated for 10 am ET release, is expected to show a decline to a 694,000 annual rate for April from 724,000 previously, according to estimates compiled by Bloomberg.

In other world markets, Japan's Nikkei closed 0.5% higher, Hong Kong's Hang Seng ended 0.2% higher, and China's Shanghai Composite finished 0.9% lower. Meanwhile, the UK's FTSE 100 fell 1%, and Germany's DAX index dropped 2.4% in Europe's early afternoon session.

In equities, shares of Uranium Energy (UEC) and Centrus Energy (LEU) were up 14% and 20%, respectively, in premarket activity following a Reuters report that Trump is expected to sign executive orders to ease regulatory requirements and enhance supply chains for the nuclear energy sector.

On the losing side, Deckers Outdoor (DECK) shares dropped 19%, a day after the company issued fiscal Q1 guidance that trailed analysts' projections. Miniso Group (MNSO) stock was down 15% after the company reported lower Q1 adjusted earnings.