BRUSSELS—The European Union fined Apple and Meta Platforms hundreds of millions of dollars and ordered the companies to comply with the bloc’s tech rules, a move that risks ratcheting up tensions with the Trump administration as EU officials pursue trade talks.

Apple and Meta were fined nearly a combined $800 million, and Apple was ordered to change aspects of its business model within 60 days.

The European Commission said the Silicon Valley companies violated the Digital Markets Act, a law meant to crimp the power of the largest tech firms.