The UN high representative, Paddy Ashdown, said that the officials he removed included parliament speaker Dragan Kalinic, a wartime ally of Karadzic, and Interior Minister Zoran Djeric.
Karadzic has been indicted by a UN tribunal at The Hague on charges of genocide for his role during the Bosnian conflict, including the Bosnian Serb massacre of up to 8,000 Muslim men and boys at Srebrenica in 1995.
The State Department's Ereli said the United Nations also is fining the Serbian Democratic Party some $600,000. "For its part and in support of the high representative's actions, the United States is freezing the assets of a Republika Srpska-owned firm and three Republika Srpska officials who have provided financial, logistical and security assistance to Radovan Karadzic," he said.
Ereli said Washington is determined to help bring Balkan war-crime suspects to justice.