The Iranian military has denied that its vessels acted unprofessionally after a US aircraft carrier was approached by armed Revolutionary Guard boats in the Strait of Hormuz.
The US navy said up to 20 Iranian vessels approached the USS George HW Bush on Tuesday, in an incident witnessed by The National's reporter on board the ship.
According to the carrier's captain, Will Pennington, some of the small Iranian vessels were loading weapons as they approached the ship at high speeds.
At one point an Iranian boat was less than 900 meters away, the US navy said.
Speaking shortly after the encounter, Rear Admiral Kenneth Whitesell, the commander of the USS George HW Bush carrier strike group, described Iran's behaviour as "unprofessional" and "harassment".
On Saturday, the spokesman of the Iranian armed forces, Brigadier General Masoud Jazayeri, responded, saying: "News disseminated by the US sources concerning unprofessional behaviour of Iranian vessels is not true".
"We warn again that the US armed forces should change their behaviour," Brig Gen Jazayeri was quoted as saying by Iran's official IRNA news agency.
He blamed the United States for any kind of unrest in the Arabian Gulf.
Following Tuesday's incident - in which one of the carrier's helicopters was also threatened by an Iranian vessel, according to the US navy - Captain Pennington said he saw the main security threat in the Gulf as the "instability and a lack of predictability we currently see from Iran".
He said this lack of predictability had been growing over the last three or four months.
Last year, there were 527 interactions between US and Iranian naval forces, 35 of which included Iranian activity deemed to be unsafe or unprofessional by US Naval Forces Central Command (Navcent).
Navcent has deemed Iran's behaviour to be unsafe or unprofessional on six occasions so far this year, including on March 4 when a group of Revolutionary Guard vessels came within 550 metres of a US navy surveillance ship, the USNS Invincible. One of the vessels came to a standstill in the path of the ship and the USNS Invincible was forced to change course to avoid collision, Navcent said.
Revolutionary Guard navy commander Admiral Mehdi Hashemi claimed the US ship had acted unprofessionally, IRNA reported on Saturday.
It "exited from international route and changed its way toward [Revolutionary Guard] navy vessels present in the region and got as close as 550 metres to Iranian vessels", Admiral Hashemi said.
Tuesday's incident involving the USS George HW Bush took place as the carrier was on its way to the northern Gulf to launch air strikes on ISIL in Iraq and Syria. Navcent said on Friday that strikes on the group had begun. The carrier also launched strikes on ISIL while in the eastern Mediterranean last month.