The U.S. Treasury Department’s Office of Foreign Assets Control (OFAC) has placed North Korea’s government agencies in charge of maritime transport, as well as half a dozen North Korean shipping companies, on the department’s sanctions list.

The U.S. Treasury Department’s Office of Foreign Assets Control (OFAC) on Tuesday placed North Korea’s government agencies in charge of maritime transport, as well as half a dozen North Korean shipping companies, on the department’s sanctions list.

By executive order of President Trump, OFAC said the sanctions are aimed at further restricting North Korea’s efforts to financially support its nuclear weapons program. The sanctions prohibit U.S. individuals and companies from having business contact with these North Korean operations.

The North Korean government agencies identified for the U.S. sanctions include the Maritime Administration and Ministry of Land and Maritime Transportation.

The six sanctioned North Korean shipping companies and their 20 North Korean-flag ships include:

• Korea Rungrado Shipping Co. and vessels _Pu Hung I_, _Rung Ra Do_, and _Yang Gak Do_.

• Korea Rungrado Ryongak Trading and vessels _Rung Ra 1_ and _Rung Ra 2_.

• Yusong Shipping Co. and vessels _Won San 2_, _Za Ryok 2_, _7-28_, _Yu Song 12_, and _Yu Song 7_.

• Dawn Marine Management Co. Ltd. and vessels _Jang Gyong_, _Kum Song 3_, _Kum Song 5_, _Kum Song 7_, and _Kum Un San 3_.

• Korea Daebong Shipping Co. and vessel _Rak Rang_.

• Korea Kumbyol Trading Co. and vessels _Kang Song 1_, _Ku Bong Ryong_, _So Baek San_, and _Rye Song Gang 1_.

“North Korea is known to employ deceptive shipping practices, including ship-to-ship transfers, a practice prohibited by United Nations Security Council Resolution (UNSCR) 2375,” which was approved on Sept. 11, OFAC said.

OFAC provided satellite photographic images on Oct. 19, showing Korea Kumbyol Trading’s vessel _Rye Song Gang 1_ performing a possible ship-to-ship transfer of oil in order to evade sanctions.

The Treasury agency also added Dandong Kehua Economy & Trade Co. Ltd., Dandong Xianghe Trading Co. Ltd., and Dandong Hongda Trade Co. Ltd. to the U.S. sanctions list. According to OFAC, these three companies–between Jan. 1, 2013 and Aug. 31, 2017–exported about $650 million worth of goods to North Korea and imported another $100 million in North Korean goods. These goods have included notebook computers, anthracite coal, iron, iron ore, lead ore, zinc ore, silver ore, lead, and ferrous products.

In addition, OFAC designated executive Sun Sidong and his company, Dandong Dongyuan Industrial Co. Ltd. (Dongyuan) as sanctioned parties.

“Sun and Dongyuan were responsible for exporting over $28 million worth of goods to North Korea over several years, including motor vehicles, electrical machinery, radio navigational items, aluminum, iron, pipes, and items associated with nuclear reactors. Dongyuan has also been associated with front companies for weapons of mass destruction-related North Korean organizations,” OFAC said.