President Trump said Wednesday that he has instructed the U.S. Navy to "shoot down and destroy" Iranian vessels that harass American ships at sea.

"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 tweeted.

The president did not reference any specific incident, but his tweet follows a tense encounter between Iranian and U.S. Navy ships in the Persian Gulf last week. The U.S. military said that 11 Iranian ships repeatedly made "dangerous and harassing approaches" of U.S. Navy and Coast Guard vessels in the Persian Gulf on Wednesday.

The U.S. Navy released a video of Iranian boats coming close to U.S. ships operating in the northern part of the Gulf.

Iran's Islamic Revolutionary Guards Corps (IRGC) acknowledged the encounter on Sunday but claimed without evidence that American forces triggered the incident, accusing the U.S. of "unprofessional and provocative actions."

Asked about Trump's tweet at a briefing later Wednesday morning, top Pentagon officials suggested it represented a warning to Tehran rather than a new order to the military.

"The president issued an important warning to the Iranians," Deputy Defense Secretary David Norquist said. "What he was emphasizing was all of our ships retain the right of self-defense, and people need to be very careful in their interactions to understand the inherent right of self-defense."

Gen. John Hyten, the vice chairman of the Joint Chiefs of Staff, added that he "liked that the president warned an adversary."

"If we see a hostile act, if we see hostile intent, we have the right to respond up to and including lethal force, and if it happens in the Gulf, if it happens in any way we will respond with overwhelming lethal force if necessary to defend ourselves," Hyten said.

Trump's threat to destroy Iranian boats harassing U.S. ships is likely to exacerbate tensions with Tehran, which have run high throughout the Trump administration.

The president's disclosure came hours after Iran claimed it had launched its first military satellite into orbit, a move that would mark an advancement of the country's ballistic missile program.

Hyten, who said the U.S. military tracked the launch, would not characterize whether the launch was successful, but said the rocket "went a very long way, which means it has the ability once again to threaten their neighbors, our allies."

Iran's nuclear ambitions have been a prime source of tension between Washington and Tehran since Trump withdrew the U.S. from the Obama-era nuclear pact known as the Joint Comprehensive Plan of Action aimed at curbing Iran's nuclear ambitions.

Still, last week's interaction marked the first heated incident in months between Washington and Tehran.

The U.S. conducted a drone strike in early January that killed Iranian Gen. Qassem Soleimani, the leader of the IRGC's Quds Force, following violent demonstrations at the U.S. Embassy in Baghdad. The Trump administration described the strike as a defensive measure aimed at preventing further attacks planned by Iran, but the move prompted questions, given a lack of information provided by the administration about Tehran's plans.

Tensions appeared to ease following Iranian missile attacks on Iraqi bases housing U.S military personnel days after the Soleimani strike. Trump declared in an address to the nation that Iran "appears to be standing down," saying no lives were lost in the attacks. The administration imposed fresh economic sanctions on Iran thereafter.

Last year, Iran also shot down a U.S. surveillance drone it claimed was flying over Iranian airspace, nearly prompting the U.S. to execute a retaliatory strike against Tehran.

Updated at 12 p.m.