The United States has imposed sanctions on one individual and three currency-exchange houses that it says are responsible for facilitating the flow of Iranian financial assistance to Huthi rebels in Yemen. The individual who was designated is the head of the Currency Exchangers Association in Sana'a. The three exchange houses are in Yemen and Turkey. U.S. Treasury Undersecretary Brian Nelson said in a statement on December 28 that the action "underscores our resolve to restrict the illicit flow of funds to the Huthis, who continue to conduct dangerous attacks on international shipping and risk further destabilizing the region."