Iran's armed forces chief of staff Ali Abdollahi issued a direct warning to Gulf states Wednesday, telling governments along the Arabian Gulf that hosting or facilitating U.S. military operations makes them parties to the conflict between Iran and the United States.

"We wish to warn that any assistance or facilitation provided to the aggressor US military amounts to participation in the US military operation," Abdollahi said, according to Iran's Mehr news agency.

The United Arab Emirates announced it was cutting economic ties with Tehran, a move the UAE linked to continued Iranian attacks on regional shipping. Abdollahi's warning to Gulf governments marks a sharp public escalation between Iran and Gulf Arab states since the war began.

War between Iran and the United States broke out Feb. 28, when U.S. and Israeli forces struck Iranian territory. Iran responded with missile and drone strikes on U.S. military bases across the region. The conflict has continued since, drawing in questions of base access, overflight rights and the posture of Gulf states caught between their security ties to Washington and their geographic exposure to Tehran.

Several Gulf governments have issued public statements insisting they would not permit the United States to use their soil as a launchpad against Iran. Abdollahi addressed those statements directly, saying Iran is tracking what actually happens at those bases regardless of what governments say publicly.

"The countries bordering the Arabian Gulf, which have issued various statements saying they would not allow the United States to use their territory against Iran, should know that we are fully aware of the situation," Abdollahi said.

He questioned the plausibility of Gulf hosts' claimed ignorance of U.S. operations. "It seems unlikely that such a large number of military aircraft, particularly refueling aircraft, could be present at regional bases without knowledge of host countries," he said. The reference to refueling aircraft was specific: tanker planes extend the reach of strike aircraft, and their presence at a base indicates offensive rather than purely defensive operations.

The U.S. Navy is rotating carrier strike groups through the region as the conflict continues. The USS George Washington is being moved to the Middle East to relieve the USS Abraham Lincoln, following reports of deteriorating living conditions aboard the Lincoln. The carrier rotation maintains continuous U.S. naval strike capacity while addressing readiness concerns aboard the departing ship.

Gulf Arab states occupy a difficult position since Feb. 28. Most host significant U.S. military infrastructure built over decades—air bases, naval facilities and pre-positioned equipment that form the backbone of American power projection in the region. At the same time, those states share the Gulf waterway with Iran, depend on it for their own energy exports and cannot insulate their populations or economies from a wider war.

The UAE's decision to sever economic ties with Tehran adds financial pressure to that calculus. Abu Dhabi and Dubai had maintained commercial relationships with Iran even through previous periods of maximum U.S. sanctions, in part because of the large Iranian diaspora community in the country and the volume of trade that moved through UAE ports. Cutting those ties is a sharper break than the UAE has made before.

Iran's response—warning the UAE and its neighbors that stated neutrality is no protection if their bases are being used—reflects a strategy of raising the cost for any state that facilitates the U.S. campaign without formally joining it. Abdollahi did not specify what action Iran would take against a country deemed to be participating, but the language of his statement made clear that Tehran views such assistance as direct involvement in the conflict.

Bahrain hosts the U.S. Navy's Fifth Fleet. Qatar's Al Udeid Air Base is the largest American air installation in the Middle East. Kuwait, Oman and the UAE each host elements of the U.S. military presence. None of those countries has formally declared a position in the Iran-U.S. conflict, and each has financial and security reasons to avoid doing so openly.