Apple is imposing unfair restrictions on developers of applications for its App Store in violation of a new European Union law meant to encourage competition in the tech industry, regulators in Brussels said on Monday.

The charges further escalated a tussle between Apple, which says its products are designed in the best interest of customers, and E.U. regulators, who say the company is unfairly using its size and considerable resources to stifle competition.

Apple is the first company to be charged for violating the Digital Markets Act, a law passed in 2022 that gives European regulators wide authority to force the largest “online gatekeepers” to change their business practices.

After initiating an investigation in March, E.U. regulators said Apple was putting unlawful restrictions on companies that make games, music services and other applications. Under the law, also known as the D.M.A., Apple cannot limit how companies communicate with customers about sales and other offers and content available outside the App Store. The company faces a penalty of up to 10 percent of global revenue, a fine that could go up to 20 percent for repeat infringements, regulators said. Apple reported $383 billion in revenue last year.

“Today is a very important day for the effective enforcement of the D.M.A.,” said Margrethe Vestager, the European Commission executive vice president in charge of competition policy. She said Apple’s App Store policies make developers more dependent on the company and prevent consumers from being aware of better offers.

E.U. regulators said the charges were preliminary and gave Apple a chance to respond. A final decision will be announced by next March.