Joe Biden's administration is imposing sanctions on a well-known Turkish businessman who is close to Turkish President Recep Tayyip Erdogan for violating U.S. restrictions on the sale of Iranian oil, Reuters reported.

The Treasury Department announced that it was imposing sanctions against Sitki Ayan and a number of companies he, his family and partners control for facilitating hundreds of millions of dollars worth of Iranian oil sales to the IRGC.

Ayan and his firms also laundered the proceeds of these sales to both the IRGC and the Lebanese Hezbollah movement, which the U.S. considers “foreign terrorist organizations.”

The sanctions include freezing any assets that Ayan or target companies may have in U.S. jurisdictions and prohibiting Americans from doing any business with them.

“Ayan’s companies have established international sales contracts for Iranian oil with foreign purchasers, arranged shipments of oil, and helped launder the proceeds, obscuring the oil’s Iranian origin and the (Guard’s) interest in the sales,” Treasury said in a statement.

Ayan, his son Bahaddin and three accomplices allegedly arranged for the sale of Iranian oil in violation of U.S. sanctions to China, other East Asian countries, the United Arab Emirates and some customers in Europe through the Ayan’s Gibralter-based ASB Group of Companies Limited holding group.

ASB owns or controls numerous firms in Turkey, Cyprus, India, and the Marshall Islands.