Four Iranian Islamic Revolutionary Guard Corps Navy (IRGCN) vessels, some of several to maneuver in what the US Navy says were ‘unsafe and unprofessional actions against US Military ships by crossing the ships’ bows and sterns at close range,’ are seen next to the guided-missile destroyer USS Paul Hamilton, in the Gulf, April 15, 2020. Photo: US Navy / Handout via Reuters.

President Donald Trump said on Wednesday he had instructed the US Navy to fire on any Iranian ships that harass it at sea, a week after 11 vessels from Iran‘s Islamic Revolutionary Guard Corps Navy (IRGCN) came dangerously close to American ships in the Gulf.

Close interactions with Iranian military vessels were not uncommon in 2016 and 2017. On several occasions, US Navy ships fired warning shots at Iranian vessels when they got too close.

While the Navy has the authority to act in self-defense, Trump’s comments appeared to go further and are likely to stoke tensions between Iran and the United States.

“I have instructed the United States Navy to shoot down and destroy any and all Iranian gunboats if they harass our ships at sea,” Trump wrote in a tweet, hours after Iran‘s Revolutionary Guard Corps said it had launched the country’s first military satellite into orbit.

The United States should focus on saving its military from the coronavirus, an Iranian armed forces spokesman said on Wednesday after Trump’s comments.

“Today, instead of bullying others, the Americans should put all their efforts toward saving those members of their forces who are infected with coronavirus,” Abolfazl Shekarchi said, according to the ISNA news agency.

The US military’s Central Command did not respond to a request for comment.

Earlier this month, the US military said 11 vessels from the IRGCN came dangerously close to US Navy and Coast Guard ships in the Gulf, calling the moves “dangerous and provocative.”

At one point, the Iranian vessels came within 10 yards of the US Coast Guard cutter Maui.

While such interactions at sea had occurred occasionally a few years ago, they had stopped recently.

Tensions between Iran and the United States increased earlier this year after the US killed Qassem Soleimani, the head of Iran’s elite Quds Force, in a drone strike in Iraq.

Iran retaliated on Jan. 8 with a rocket attack on Iraq’s Ain al-Asad base where US forces were stationed. No American troops were killed or faced immediate bodily injury, but more than 100 were later diagnosed with traumatic brain injury.