The United States announced on Tuesday (December 12) that it had imposed sanctions on more than 250 entities and individuals. The entities and individuals come from countries such as China, Turkey, and the United Arab Emirates, and are accused of playing a key role in Russia's continued invasion of Ukraine. Bloomberg reported that what was sanctioned on Tuesday was what the U.S. agency called the "Russian Sourcing Network," a loose alliance of companies that maintains a strong interest in cutting-edge Russian technology in violation of U.S. sanctions and export controls. Despite a series of sanctions following Moscow's war on Ukraine, the United States and its allies have struggled to prevent related products from entering the Russian market. U.S. Treasury Secretary Janet Yellen said in a statement that the sanctions would "continue to tighten constraints on third-country businesses and networks that voluntarily provide Russia with the inputs it urgently needs to expand and maintain Russia's military-industrial base." 
According to the U.S. Treasury Department, one of the sanctioned procurement networks operates in China, Hong Kong and Pakistan and consists of four entities and nine individuals. This sourcing network continues to supply Russian, Chinese-made, and technology, including multimillion-dollar semiconductor manufacturing equipment to Russian customers, as well as drones and related components. According to a statement from the U.S. Treasury Department, this procurement network is Chinese citizen Hu Xiaoxun and his private defense company, Jarvis HK Coltd. A number of Turkish individuals and companies have been sanctioned by the United States for supplying other commonly used components such as ball bearings, electronic integrated circuits, and navigational aids. The U.S. Treasury Department says the equipment and components are used to keep the Russian war machine running. Several UAE-based companies have also been sanctioned for supplying aircraft parts and equipment to Russian companies. 
The U.S. Treasury Department said a South Korean national, Dongjin Lee, was in charge of procurement for a sanctioned Russian company**. The U.S. Department of Commerce also sanctioned a Swiss-based electronics company, Thamestone SA. Also on the sanctions list is Singapore-based Micro Electronics Technologies Pte Ltd. The United States has also imposed sanctions on several shipping companies accused of helping to transport arms from North Korea to Russia. 