Washington, Sept. 9 -- The United States Department of the Treasury has placed 27 Iranian airlines on its Specially Designated Nationals List, effectively targeting every remaining commercial carrier in the country as part of an intensified pressure campaign against Tehran.

In a press statement issued on Tuesday, the department stated that "Iran's commercial airlines have long supported the Iranian regime's destabilising activities." It added that the Islamic Revolutionary Guard Corps has routinely utilised ostensibly private airlines to procure and transport weapons, as well as to ferry personnel.

Washington initially sanctioned the Iranian carrier Mahan Air in October 2011, subsequently targeting several companies acting as its genera...