WASHINGTON 

The US sanctioned a Shanghai-based firm Tuesday for allegedly working on behalf of Iran's Mahan Air airliner.

The Treasury Department said Saint Logistics Limited was blacklisted for "acting as a general sales agent (GSA) for or on behalf of Iranian airline Mahan Air," which Washington previously sanctioned in 2011 for its support of the external operations branch of Iran's Islamic Revolutionary Guards Corps.

A GSA is a third-party company that provides services to an airline.

“The Iranian regime is using Mahan Air to support an illegitimate and corrupt regime in Venezuela, just as it has done for the regime in Syria and for terrorist proxy groups throughout the Middle East,” said Treasury Secretary Steven Mnuchin.

“We will not hesitate to target those entities that continue to maintain commercial relationships with Mahan Air,” he added.

The US accuses Saint Logistics of providing various services to Mahan, including booking freight flights for the airliner between China and Iran.

Any property owned by Saint Logistics subject to US jurisdiction is frozen and US persons are generally prohibited from conducting business with the firm, and anyone who does conduct business with the company may then be subject to designations.