Oleg Sharan/AP Photo

A top Russian official angrily called Madonna a former prostitute today after the pop diva came out in support of a Russian punk rock band in jail for protesting President Putin.

"Every former [expletive] seeks to lecture everyone on morality as she gets older. Especially during tours and gigs abroad," Deputy Prime Minister Dimitry Rogozin wrote on Twitter.

Madonna spoke up for the all female Russian punkers Pussy Riot during a Moscow concert Wednesday. She is playing again tonight in St. Petersburg where she has pledged to use the venue to speak out against the city's harsh new anti-gay laws, which penalize speaking about homosexuality around minors.

The U.S. Embassy in Moscow took the unusual step of issuing a warning to American citizens who planned to attend the concerts that they could be the target of unspecified attacks.

The Material Girl took a break from her performance Wednesday to speak out against the detention of three members of the all female Russian punk band that is on trial for an anti-Putin performance.

The group is on trial for their unauthorized "punk prayer" performance on the altar of Moscow's Christ the Savior Cathedral which called for divine intervention to deliver Russia from Vladimir Putin.

The three women face up to seven years in prison if convicted on charges of "hooliganism" for their performance in the cathedral, which has also drawn criticism from the Russian Orthodox Church.

"I know there are many sides to every story, and I mean no disrespect to the church or the government. But I think that these three girls - Masha, Katya, Nadya - I think that they have done something courageous. I think they have paid the price for this act. And I pray for their freedom," she said, according to the New York Times.

Rogozin had an angry message for Madonna on Twitter today.

"Either take off your cross, or put on your knickers," he wrote, according to the BBC.

In speaking out against the band's detention, Madonna joined artists like Sting, the Red Hot Chili Peppers, and Franz Ferdinand who have all used recent concerts in Russia to call for their release.

Addressing the audience from the stage, Madonna also stressed the value of free speech for artists. She reportedly donned a colored baklava knit cap, Pussy Riot's signature outfit, and also came out wearing a black bra with the band's name written on her back.