Iran and US warships in 'unsafe' encounter in Gulf strait

Four Iranian warships sped close to two US guided missile destroyers with weapons uncovered in the Strait of Hormuz in an "unsafe and unprofessional" encounter, US defence officials said late on Wednesday. 

The USS Nitze shot warning flares, sounded its whistles and attempted unsuccessfully to communicate with the Iranian boats during Tuesday's incident, US Central Command spokesman Kyle Raines said in a statement.

He added that the Iranian vessels came within 300 yards (275 metres) of the American destroyer. The Nitze was accompanied on its mission by the USS Mason, another destroyer.

The encounter occurred in international waters in the strait, a vitally important choke point with Iran to its north and the United Arab Emirates to the south.

The destroyer had to change course to avoid a possible collision, even though it was near offshore oil rigs. 

"Nitze also changed its course multiple times in close proximity to offshore oil rigs in an attempt to maintain separation and better understand Iranian intentions," Raines said Wednesday.

"Eventually, the Iranian vessels slowed before proceeding outbound."

When asked about the matter, Iran's defence minister, Hossein Dehghan, said his country's "naval units have the duty of safeguarding the country's security in the sea and the Persian Gulf".

"Naturally these boats constantly monitor the developments and foreign vessels' movements and naturally this happens in the waters of our own country. If any foreign vessel enters our waters, we will give them a warning and if it is an act of aggression, we will confront them," he said.

This was not the first maritime scare between the United States and Iran.

In January, the Iranian navy briefly captured the crews of two US patrol boats that had, through a series of blunders, strayed into Iranian territorial waters. 

The 10 American sailors were released within 24 hours.

"We assessed the interaction as unsafe and unprofessional due to the Iranian vessels not abiding by international law and internationally recognised maritime rules of the road as well as their high rate of closure of Nitze and disregard of multiple warnings by the ship's whistle and flares," Raines said of the latest incident.

"The US navy continues to remain vigilant and is trained to act in a professional manner, and we expect the same of all nations with professional maritime forces."