The US has extended sanctions on the Belarus President Alexander Lukashenko, following an election many Western governments say was rigged.
President Lukashenko has been in power since 1994
All Mr Lukashenko's assets in the US have been frozen and Americans are now forbidden from doing business with him.
The sanctions, which are part of a response coordinated with the EU, also apply to nine other Belarus officials.
The US imposed a travel ban on Mr Lukashenko last month, following his controversial re-election in March.
President George W Bush issued an executive order on Monday detailing the sanctions, which came into effect immediately.
'Stain of dictatorship'
White House spokesman Tony Snow cited the "fraudulent presidential election in March 2006, repression of post-election demonstrations and continued detention of activists and opposition supporters".
The US attacked Mr Lukashenko for jailing opposition activists
The EU has already frozen assets held in the EU by Mr Lukashenko and 35 of his top aides and imposed a visa ban on the president and 30 officials.
The US sanctions extend to the minister of justice, the national security adviser, the minister of internal affairs, the chief of the Belarusian KGB; the chief of the central commission for elections and national referendums and the head of the Belarusian state media company.
In addition, Washington is concerned that some opposition leaders have been detained since the poll.
Earlier, President Bush gave reformers in Belarus his support, describing them as "seeking to erase the stain of dictatorship from Europe".
In the March election Mr Lukashenko was returned to office for a third term with 83% of the vote, but the Organisation for Security and Co-operation in Europe, Europe's main election monitoring body, said the elections were "severely flawed".
The result sparked demonstrations in the capital, Minsk, and hundreds of opposition supporters were arrested.