The United States on Wednesday imposed new sanctions on Iran's biggest airline and its shipping industry, accusing them of transporting lethal aid from Iran to Yemen and weapons of mass destruction proliferation.
Washington targeted three general sales agents of Mahan Air over the role the airline has played in weapons of mass destruction proliferation, US Secretary of State Mike Pompeo told reporters.
Also blacklisted was an Iranian shipping network involved in smuggling lethal aid from Iran to Yemen on behalf of the Islamic Revolutionary Guards Corps (IRGC) and its elite foreign paramilitary and espionage arm, the Quds Force, the US Treasury said.
The new sanctions come just days after a weekend prisoner swap between the historic foes, a rare act of cooperation since tensions escalated after US President Donald Trump withdrew from the 2015 Iran nuclear accord.
The latest sanctions target Iranian businessman Abdolhossein Khedri and his companies Khedri Jahan Darya Co and Maritime Silk Road LLC for alleged shipping operations on behalf of the IRGC-QF.
Mahan Air has previously been blacklisted for alleged support it has provided to the IRGC-QF, Hezbollah and Syrian President Bashar al-Assad, according to a Treasury Department statement.
The Treasury sanctions freeze any US assets of those targeted and prohibit Americans from doing business with them.
"The Iranian regime uses its aviation and shipping industries to supply its regional terrorist and militant groups with weapons, directly contributing to the devastating humanitarian crises in Syria and Yemen," Treasury Secretary Steven Mnuchin said in a statement.
"Aviation and shipping industries should be vigilant and not allow their industries to be exploited by terrorists." 
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