FNA- Islamic Revolution Guards Corps (IRGC) Deputy Commander for political affairs Brigadier General Rasoul Sanayee Rad warned the US that its naval forces' unprofessional behavior in the Persian Gulf would end up in grave consequences.

"The Americans' moves might be a type individually decided actions and not measures coordinated at the high level; another possibility is that the Americans are after testing our behavior by maneuvering," Sanayee Rad said on Saturday after the US naval forces made "provocative and unprofessional" moves against the IRGC vessels in the Persian Gulf for a second time in a week.

"We caution them to end such provocative and unprofessional moves because they are to account for such deeds," he added.

"The Americans' actions are rather unprofessional behavior shown without no respect for the regional conditions and can have heavy consequences for them and the region," Sanayee Rad warned.

His remarks came after the IRGC Navy's fourth naval zone announced in a statement on Saturday that the US naval forces have for the second time in a week made a provocative move in the Persian Gulf.

"The USS Nimitz aircraft carrier and an accompanying cruiser flew a helicopter and approached the IRGC's vessels on Friday 4pm while they were monitored and traced by the missile-launching frigates of Zolfaqar Naval regiment of the IRGC Navy's fourth zone in Resalat oil-gas region (in the middle parts of the Persian Gulf)," the IRGC Navy said.

It added that the incident happened a few days after another US cruiser had fired warning shots at an Iranian vessel in the Northern parts of the Persian Gulf.

The statement blasted the "Americans' provocative and unprofessional move", and said the IRGC vessels continued their mission in the region after the US warships fired warning flares, forcing the US aircraft carrier and cruiser to leave the region.

The IRGC Navy also said on Tuesday that it has frustrated a provocative move by a US navy ship in the Persian Gulf after it allegedly fired warning shots at an Iranian vessel.

"This morning, a US Navy ship in the Northern part of the Persian Gulf sailed towards an IRGC Navy�s patrol ship, which was patrolling in international waters, and fired two shots into the air with the aim of provocation and intimidation," the IRGC said in a statement.

The IRGC Navy�s ship paid no attention to the �provocative and unprofessional� move by the US Navy and continued with its mission, it added.

"After a while, the US Navy ship left the area," the IRGC said.

The IRGC issued the statement after some Western media outlets quoted a US official as saying that a US Navy ship had fired warning shots toward an Iranian vessel near the Northern Persian Gulf on Tuesday after the Iranian vessel came within 150 yards (137 meters) of it.

The official, speaking on the condition of anonymity, claimed the USS Thunderbolt fired the warning shots after the Iranian vessel ignored radio calls and the ship's whistle.

Iran has also repeatedly warned that any act of transgression into Iran�s territorial waters would be met with an immediate and befitting response.

A US Navy ship and three British Royal Navy boats were forced to change course when several Iranian fast-attack vessels approached them in the Strait of Hormuz in March.

In January last year, Iran's Navy arrested the crews of two US patrol boats that had trespassed on Iranian territorial waters. Iran released them after establishing that they had done so by mistake.