Iran Air has been used by Tehran’s powerful Islamic Revolutionary Guard Corps to “transport military related equipment” since 2006, the Treasury Department said in a statement.
“Rockets or missiles have been transported via Iran Air passenger aircraft, and IRGC officers occasionally take control over Iran Air flights carrying special IRGC-related cargo,” the statement said.
“Additionally, commercial Iran Air flights have also been used to transport missile or rocket components to Syria.”
Iran Air has been under US sanctions since 1995 that have prevented any sale of Boeing or Airbus aircraft or spare parts to it, and as a result it has become one of the most dilapidated airlines in the world.
The airline serves 35 international destinations in Asia and Europe. In July 2010, the European Union banned most of Iran Air’s planes from its airspace for safety reasons.
Along with the sanctions on Iran Air, the Treasury Department imposed sanctions against Tidewater Middle East Company, a port operator owned by the Revolutionary Guards.
Ports managed by Tidewater had been used by Tehran to export weapons in violation of UN Security Council resolutions, the Treasury said.
Secretary of State Hillary Clinton and Treasury Secretary Timothy Geithner condemned Iran’s “dangerous activities” in a joint statement about recent measures that Washington has taken to isolate Tehran.
“The IRGC’s illicit activities and its increasing displacement of the legitimate Iranian private sector in major strategic industries, including in the commercial and energy sectors, are deeply troubling,” they said.
In a separate move on Thursday, US authorities filed charges against firms in France and the United Arab Emirates alleging they conspired to export components for attack helicopters and fighter jets to Iran without a license.
Earlier this week, the Treasury Department slapped sanctions on 10 shipping companies and three individuals linked to Iran’s national shipping line, the Islamic Republic of Iran Shipping Lines, or IRISL.
IRISL itself has been sanctioned since 2008 for providing services to Iran’s Ministry of Defense and Armed Forces Logistics, which oversees the country’s ballistic missile program.
The United States has intensified its efforts to isolate Iran since June 2010, when the United Nations Security Council imposed a fourth round of sanctions on Tehran.
Washington has pressed the sanctions because of concerns over Iran’s nuclear program, which it fears is aimed at building an atomic bomb, as well as Tehran’s support for radical Islamist groups like Hezbollah.
Tehran denies that its nuclear program is military in nature.
