Stocks were mixed in early trading on Monday after President Donald Trump over the weekend issued 30% tariffs on the European Union and Mexico, rekindling tensions with two of the largest U.S. trade partners and threatening to raise consumer prices.

Italy's foreign minister warned that, while he hopes for successful negotiations, the EU will respond resolutely to Trump's latest tariff threat.

Von der Leyen's decision to resist immediate retaliatory measures points to the European Commission's desire to avoid a spiralling tit-for-tat escalation.