WASHINGTON, March 17 (Reuters) – The United States on Thursday imposed sanctions on Belgian businessman Alain Goetz and a network of companies tied to him that it accused of being involved in the illicit movement of gold from Democratic Republic of Congo.

The U.S. Treasury Department, in a statement, said among the targets was the African Gold Refinery in Uganda, which Goetz operates, and several other companies he owns or controls. It accused Goetz and the companies of being involved in illegal gold exports valued at hundreds of millions of dollars per year.

In a statement, Goetz said his inclusion on the U.S. sanctions list “seems to be based on misinformation”. He said he has not been to Congo in more than 20 years and has not kept any active contacts within Congo.

Goetz said he was asked to set up East Africa’s first gold refinery in 2014, adding that “nothing has made me prouder than to see the impact that African Gold Refinery has had on the gold industry in the Great Lakes region”.

The Treasury said a network of armed groups, smugglers and companies generate illicit revenue from the gold industry through forced labor, smuggling or other means. It said the illicit movement of gold provides revenue to armed groups that threaten peace and security in Congo.

“Conflict gold provides the largest source of revenue to armed groups in eastern DRC where they control mines and exploit miners,” the Treasury’s under secretary for terrorism and financial intelligence, Brian Nelson, said in the statement.

“Alain Goetz and his network have contributed to armed conflict by receiving DRC gold without questioning its origin.”

The Treasury said Goetz’s network sources gold from Congo, Kenya, South Sudan and Tanzania.

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Goetz said the Treasury’s Office for Foreign Assets Control (OFAC) had presented no documented evidence to back up their claims, and that he was confident this “mistake” would be swiftly rectified.

The Ugandan government did not immediately reply to a request for comment.

Others designated on Thursday that the Treasury said were owned or controlled by Goetz include United Arab Emirates-based Agor DMCC and UAE-based Goetz Gold LLC.

Agor did not immediately respond to a request for comment.

Goetz Gold LLC and the African Gold Refinery could not immediately be reached for comment.

The Treasury said that since 2016, the African Gold Refinery, considered one of the largest gold refineries in Africa, has sourced illicit gold from mines in regions of Congo that are controlled by armed groups, including the Mai-Mai Yakutumba and Raia Mutomboki militia.

Thursday’s move freezes any U.S. assets of those designated and generally bars Americans from dealing with them.

“This strong action by the U.S. will send shockwaves throughout the global gold supply chain,” Sasha Lezhnev, policy consultant at non-governmental organisation The Sentry, said.

“Turning a blind eye to conflict gold now carries a heavy price.”

(Reporting by Daphne Psaledakis, Additional reporting by David Lewis and Elias Biryabarema; Editing by Tim Ahmann and Hugh Lawson)