Washington - The United States will today formally announce an end to US economic sanctions on Yugoslavia, a White House official said yesterday. It will continue to impose sanctions on some 81 Serbs, including the former president, Mr Slobodan Milosevic, his family and members of his entourage, the official said. The decision is one of the last executive orders signed by President Clinton, who will step down tomorrow as President-elect George W. Bush assumes the nation's highest office.