WASHINGTON The U.S. Treasury Department said on Wednesday it had imposed sanctions on 21 Iranian and foreign nationals and entities for their involvement in financial networks to benefit Iran's defense ministry and other parts of its military.

In a statement, the Treasury said those sanctioned helped generate funds for Iran’s Ministry of Defense and Armed Forces Logistics, the Iranian Armed Forces General Staff (AFGS), and the Islamic Revolutionary Guard Corps-Qods Force (IRGC-QF).

"Iran generates the equivalent of billions of dollars via commodity sales to fund its destabilizing regional activities and support of multiple regional proxy groups, including Hamas and Hizballah," it said, referring to the Islamist Palestinian group and the Lebanese Shi'ite armed force and political party.

The Treasury said the Iranian military used "intricate networks of foreign-based front companies and brokers to enable these illicit commercial activities."

Washington wants to crack down on Iran's evasion of previous U.S. sanctions and cut off support for Iran-backed Palestinian militant group Hamas following its attack on Israel last month.

Those sanctioned include Iran-based companies Sepehr Energy Jahan Nama Pars Company and Pishro Tejarat Sana Company as well as Iranian citizens Majid A’zami, Elyas Niroomand Toomaj and Seyyed Abdoljavad Alavi.

Treasury also put sanctions on two Hong Kong-based firms, accusing Puyuan Trade Co Limited of brokering sales of tens of millions of condensate, a form of ultralight crude oil, to HK Sihang Haochen Trading Limited.

Also sanctioned were several United Arab Emirates-based firms.

These included Unique Performance General Trading LLC, to which Sepehr Energy agreed to sell Iranian light crude for delivery in China, and OPG Global General Trading Co LLC, which offered to sell crude and gasoline on Sepehr Energy's behalf to Gulf customers for onward shipment to Europe, the Treasury said.

In addition, the Treasury said it had sanctioned Dubai-based JEP Petrochemical Trading LLC, which paid Dubai-based Future Energy Trading LLC the equivalent of more than $400 million to buy Iranian oil from Sepehr Energy.

Three other companies restricted were Dubai-based A Three Energy FZE along with Sharjah-based brokers Tetis Global FZE and Royal Shell Goods Wholesalers LLC, which Sepehr Energy used to enable sales of Iranian commodities to foreign buyers.

In addition, the Treasury said imposed sanctions on four companies and three individuals for supporting illicit financial networks on behalf of the IRGC-QF.

It named the companies as UAE-based Transmart DMCC and Solise Energy (FZE) and as Singapore-based MSE Overseas PTE Ltd and Sealink Overseas PTE Ltd and the individuals as Zabi Vahap, Adelina Kuliyeva and Mehboob Thachankandy Palikandy.

(Reporting by Arshad Mohammed and Daphne Psaledakis; Editing by Grant McCool)