Russia on Monday called on Belarus to immediately release its citizens detained after riots quashed by President Alexander Lukashenko following his re-election.
"The Russian side insists on an urgent release of several Russian citizens detained on December 19 in Minsk," the Russian foreign ministry said in a statement.
"Delaying a solution to this matter will negatively affect the general atmosphere of bilateral Russian-Belarussian ties," the statement said.
A Russian embassy official in Minsk said 11 nationals remained in detention on Monday.
Belarus arrested more than 600 people on the night of December 19 after a massive rally gathered in central Minsk to protest presidential elections that Western observers said fell well short of democratic norms.
Belarussian police also launched sweeping raids on opposition homes and offices as part of its crackdown on protests following Lukashenko's re-election to a fourth-term, rights groups said.
The crackdown on protesters and the poor quality of the election drew strong criticism from Europe and the United States but Russia said the vote was Belarus's "internal affair."
On Saturday, Russian President Dmitry Medvedev finally congratulated Lukashenko on his re-election even though his statement was conspicously dry.