Iran’s Supreme Leader Ayatollah Ali Khamenei warned on Sunday that any U.S. attack on Iran would trigger a wider regional conflict, according to state media, as tensions between Tehran and Washington continue to escalate.

The warning comes as the United States has strengthened its naval presence in the Middle East following repeated threats by President Donald Trump to intervene if Iran refuses to agree to a nuclear deal or fails to halt the killing of protesters.

Referring to U.S. military deployments, Khamenei said Iran would not be intimidated by such moves. “The Iranian nation will not be frightened by these threats,” he was quoted as saying. “We are not the initiators and do not seek to attack any country, but the Iranian nation will deliver a strong response to anyone who attacks or harasses it.”

Despite the heightened rhetoric, Tehran has signalled that diplomacy remains possible, saying it is prepared for “fair” negotiations that do not undermine its defensive capabilities.

The U.S. Navy currently has six destroyers, one aircraft carrier, and three littoral combat ships deployed in the region.

The tensions coincide with recent protests in Iran that began in late December over economic grievances and evolved into the most serious political challenge to the Islamic Republic since its founding in 1979. The demonstrations have since subsided following a crackdown.

Official figures put the death toll linked to the unrest at 3,117, while the U.S.-based Human Rights Activists News Agency (HRANA) said it has verified at least 6,713 deaths. Reuters said it was unable to independently confirm the figures.

Khamenei described the protests as a “coup,” saying the aim of what he called “sedition” was to target the country’s governing institutions, according to state media.