Japan's competition regulator has told Google (GOOGL, Financials) to stop pressuring smartphone makers into prioritizing its own apps and services, a move that could reshape how major tech firms operate in the country.

The Japan Fair Trade Commission on Tuesday issued a cease and desist order against the U.S. tech giant — the first time Japan has taken formal action against one of Silicon Valley's biggest names over antitrust concerns.

Regulators say Google struck deals with phone manufacturers that effectively sidelined rival services, requiring Android phones to give Google's search engine and apps top billing. Those contracts, the watchdog said, likely gave Google an unfair advantage while making it harder for competitors to get a foothold.

As part of the order, Google must bring in a third-party monitor to review and report on its business practices.

In response, the company said it was disappointed with the decision but added that it would work with the commission to ensure Android remains a competitive and open platform.

The case is part of a growing global push to rein in the power of tech platforms, especially when it comes to how they bundle services and dominate user access points. Regulators in the European Union and the United States have brought similar cases against Google and other major players over how their software ecosystems are structured.

Japan's move adds pressure on Big Tech to rethink how they do business in international markets, especially where local regulators are becoming more assertive about leveling the playing field.