The US Treasury on Thursday said it blacklisted Syria's largest mobile phone operator and a chain of duty free shops because they are owned by a Syrian businessman previously targeted by the United States. Syrian tycoon Rami Makhlouf, whose assets were frozen by the United States in February, has a stake in Syriatel, the country's largest mobile phone operator, and in Ramak, a chain of duty free shops, the Treasury Department said. “Rami Makhlouf uses his access to high-level Syrian government insiders to enrich himself at the expense of the Syrian people,” Adam Szubin, director of the Office of Foreign Assets Control, said in a statement. The Treasury said designating Syriatel and Ramak will prevent the two companies from doing business with US banks or American consumers. On Feb. 21, Treasury levied sanctions against Makhlouf, a cousin of Syrian President Bashar Al-Assad, saying he benefited from corruption in the Syrian government. He is considered Syria's most powerful businessman. “We will continue to target Makhlouf and his commercial empire as well as others who follow in his footsteps,” Szubin said. The Bush administration expanded sanctions against Syria to target individuals profiting from Syrian government corruption.