Iran and Pakistan Navies joint exercise near Straight of Hormuz

Docked at Bandar Abbas: PNS Hashmat (S135) Hashmat class (Fr Agosta-70 type) diesel attack submarine (SSK)

According to Islamic Republic News Agency:

Naval forces of Iran and Pakistan began a joint military exercise in east of Hormuz Strait in Persian Gulf on Tuesday participated by the selected units of the Navy forces of both countries.

The Pakistani fleet comprises Pakistan Navy Ship (PNS) RASADGAR a Pakistani built Small Tanker cum Utility Ship (STUS), PNS QUWWAT a Pakistani built Missile Boat and a French made submarine PNS/M HASHMAT.

The Pakistani flotilla docked at the provincial capital city of Bandar Abbas in Hormuzgan Province on April 5...

Docked at Bandar Abbas: PNS Quwwat (P 1028) Jurrat class fast attack craft (missile)

Docked at Bandar Abbas: PNS Rasadgar (23)  small tanker cum utility ship (STUS)

Video, IRIB News:

Routine Iran naval surveillance of USN carrier force transiting the Straight of Hormuz

According to the Associated Press:

Iranian patrol boats and aircraft shadowed a U.S. aircraft carrier strike group as it transited the Strait of Hormuz on Tuesday. 

[...] 

But officers onboard the USS Abraham Lincoln said there were no incidents with Iranian forces and described the surveillance as routine measures by Tehran near the strategic strait, which is jointly controlled by Iran and Oman. 

[...] 

[J]ust after the Lincoln rounded the "knuckle" — the nub of Oman jutting out at the southern end of the strait — an Iranian patrol plane buzzed overhead. Another patrol boat was waiting further down the coast, said Rear Adm. Troy Shoemaker, commander of the Abraham Lincoln Carrier Strike Force. 

[...] 

He predicted before the transit that the Iranians would likely keep a close eye on the Lincoln throughout its passage, including with ground-based radars. He wasn't surprised by the attention from Iranian forces. 

"We would do the same things off the coast of the United States ... It's more than reasonable. We're operating in their backyard," [USN Rear Adm. Troy Shoemaker said]. 

File photo: Rear Adm. Troy Shoemaker

File photo: USS Abraham Lincoln (CVN 72) 

Photos: World News and United States Navy

Velayat-90 Military Maneuvers (4)

click photos to enlarge

Iran Navy Agusta AB-212 ASW and SH-3D Sea King (AS-61) helicopters

Iranian commando frogman dropped from Agusta SH-3D Sea King

Iranian commando frogman team in inflatable rubber raiding craft

Assortment of FB type and Ashura class inshore patrol craft (PBF)

and a Sea-Doo RXT-X 255 watercraft, all manned by IRI Marines

FB type equipped with 107 mm MLRS in action

Late model Sea-Doo RXT-X 255 watercraft

Inshore patrol craft firing HM-23 16 round 122mm MLRS

Gunners loading a 16 round 122mm MLRS

IRI Marines armed with G3A4 battle rifles

IRIAF McDonnell Douglas F-4E Phantom II fighter-bomber

IRIN Commander Read Admiral Sayyari with a commodore and lieutenant junior grade

Iran's potential response to USN shipping interdiction

By Mark Pyruz

IRIS Jamaran (76) and IRIS Alborz (72)

At his latest press conference, President Ahmadinejad today warned that any inspections of its ships related to sanctions could provoke a response by the Islamic Republic of Iran.

"If they make the slightest mistake we will definitely respond," Ahmadinejad said.

Some observers have criticized Iran's naval forces for being relatively weak in overall strength, particularly when compared to the US Navy Fifth Fleet in the Persian Gulf waters. They also point out Iran's naval forces are less than state of the art. But these naval forces, while relatively small and somewhat under-equipped, are adequately suited for selectively targeted merchant shipping interdiction, including boarding, inspection and search of a ship at sea; second, taking measures including any combination of arresting the vessel, arresting persons aboard or seizing cargo.

Naval vessels and armed forces of the Islamic Republic of Iran Navy (IRIN) in the Persian Gulf and Gulf of Oman, and the Islamic Revolutionary Guard Corps Navy (IRGCN) in the Persian Gulf, are able to conduct such operations. These include the Alvand class frigates, Moudge class frigate and Thondar class missile crafts.

Lineup of four IRGCN Thondar class missile craft

Of course, such actions are extremely risky for the Islamic Republic, as escalation could quickly follow. However, the same risks apply to the United States, which could lead to a cascading of events resulting in the breakout of open hostilities. Just the temporary stoppage or seizure of a merchant ship by Iranian naval forces, alone, particularly near the Straight of Hormuz, could lead to a dramatic spike in shipping insurance rates and the price of crude oil. It would likely even prompt some form of active USN escort coverage.

The previous round of sanctions technically called for a potential inspection regimen of "suspected" Iranian related shipping, but it was not acted upon in a meaningful or provocative manner. The ball is again in the court of the United States, on whether or not we'll see such a turn of events associated with this latest round of sanctioning.

Trio of Kaman class (Combattante IIB type) missile boats