Deputy Prime Minister Dmitry Rogozin of Russia has rounded on Madonna for defending Russian punk band, Pussy Riot.
Using his official Twitter account, Mr Rogozin accused the American singer of moral lecturing, telling her: "Either take off your cross, or put on your knickers."
The band is on trial after performing a song attacking Vladimir Putin in front of the altar of the main cathedral in Moscow on 21 February.
Maria Alyokhina, 24, Nadezhda Tolokonnikova, 22, and Yekaterina Samutsevich, 29, are accused of hooliganism.
During her show in Moscow on Tuesday, Madonna told her fans the three members of Pussy Riot had done something courageous and that she was praying for their freedom.
"I know that everyone in this auditorium, if you are here as my fan, feels they have the right to be free," she said.
The BBC reports she also took off her shirt to reveal the band's name written on her back.
Mr Rogozin also wrote: "Every former w.... seeks to lecture everyone on morality as she gets older. Especially during tours and gigs abroad."
The BBC reports he did not write the word in full, but there is little doubt in Russia that he was using a version of the word "whore", which is considered one of the most offensive terms that can be used against a woman in Russia.