The United States has announced tougher visa rules for international students, exchange visitors, and foreign journalists.

Under the new policy, F and J visas will be limited to a maximum stay of four years, replacing the current system that allows holders to remain for the duration of their studies or programs.

Foreign journalists on I visas will be allowed to stay for 240 days, while Chinese journalists will face a stricter 90-day limit.

The Department of Homeland Security says the changes are aimed at strengthening immigration oversight and improving visa compliance.

The new regulations are expected to take effect 60 days after publication, subject to congressional review.

Critics warn the changes could create uncertainty for international students, universities, and media organisations operating in the United States.