WASHINGTON, Jan. 13 (Xinhua) -- The U.S. Treasury Department on Thursday slapped sanctions on 24 shipping companies affiliated with the Islamic Republic of Iran Shipping Lines (IRISL) and two entities that are subordinates of Iran's Aerospace Industries Organization (AIO).

"Today's actions build on Treasury's efforts to expose the financial and corporate underpinnings of IRISL and AIO, two entities that face international sanctions for their involvement in Iran's missile programs," said the Treasury Department in a statement.

The department said the actions are designed to curb efforts by Iran to evade U.S. sanctions and use "front companies, subsidiaries, affiliates, and other deceptive measures" to protect IRISL and AIO.

"IRISL is under tremendous financial pressure from international sanctions, and it is going to extreme lengths to obscure its network and the ownership of vessels," Undersecretary for Terrorism and Financial Intelligence Stuart Levey said in the statement.

"Today's designations expose the latest in a string of deceptive measures Iran is taking to continue its illicit conduct, " he added.

This is the latest round of financial sanctions taken by the United States to isolate Iran from the international financial system.