Iran's armed forces warned Gulf countries against assisting the US military on Wednesday, hours after the United Arab Emirates announced it was severing economic ties with Tehran following new attacks on shipping. The Gulf is dotted with US military installations, including in the UAE, which said on Tuesday that Iran had fired two ballistic missiles at vessels off its coast. Despite a recent lull in hostilities between the United States and Iran, the Strait of Hormuz -- which Tehran has blockaded -- remains a flashpoint, and attacks on commercial ships have continued. A framework US-Iran deal aimed at reopening the vital trade corridor collapsed, and although both sides recently said messages were being exchanged, US President Donald Trump on Tuesday insisted talks were off, taunting Iran with a social media post depicting the strait as a "NEW U.S. Territory". Iranian armed forces chief of staff Ali Abdollahi, according to the Mehr news agency, warned "any assistance or facilitation provided to the aggressor US military amounts to participation in the US military operation". The conflict broke out on February 28 with US-'Israeli' attacks on the Islamic republic, which retaliated with missile and drone strikes across the region. Since the start of the war, many Middle Eastern countries have said they would not allow the United States to use their territory as a launchpad for attacks, though Abdollahi cast doubt on those promises. "It seems unlikely that such a large number of military aircraft, particularly refuelling aircraft, could be present at regional bases without knowledge of host countries," said Abdollahi, adding Gulf countries "should know that we are fully aware of the situation".