26 July, 2017
The USS Thunderbolt, a Navy patrol craft, was conducting a coalition exercise in the worldwide waters when the Iranian vessel approached, according to the Navy.
This episode is only the latest in a series of clashes between american ships and vessels iranians.
The video shows the Iranian boat coming near the bow of the U.S. ship, which the Navy said was within 150 yards.
"The Iranian vessel's actions were not in accordance with the internationally recognized".
It happened at around 03:00 local time (00:00 GMT), as the Iranian ship began to approach the USS Thunderbolt.More news: Australian woman who called 911 shot dead by Minneapolis police
Of the incidents a year ago, the worst involved Iranian forces capturing 10 USA sailors and holding them overnight.
On April 26, the U.S. Navy confirmed that a U.S. guided-missile destroyer fired a warning flare toward an Iranian Revolutionary Guard vessel.
The U.S. Navy recorded 35 instances of what it describes as "unsafe and/or unprofessional" interactions with Iranians forces in 2016, compared to 23 in 2015. Iran and the USA frequently have tense naval encounters in the Persian Gulf.
Both countries are involved in the fight against the Islamic State militant group (ISIS) in Iraq and Syria but back different factions, The U.S.is also a key ally of Iran's regional rival, Saudi Arabia, which supports forces that regularly clash with Iran-backed movements in Syria and Yemen.
Naval incidents with Iran are not entirely unusual, though ones involving shots fired are.
The boats had been on their way from Kuwait to Bahrain and experienced engine trouble, according to the U.S. Navy.