Anti-Putin punks Pussy Riot were sentenced to two years each on Friday over a protest in Moscow, sparking anger among their supporters. Judge Marina Syrova ruled the three women's February performance of a "punk prayer" urging the Virgin Mary to "drive Putin out" was "hooliganism aimed at inciting religious hated."

"Today the regime has both openly and cynically committed a criminal act," opposition lawmaker Dmitry Gudkov told journalists outside a Moscow court, adding that the trial was an example of political "repression" that risked triggering "civil war".

But the Orthodox Church appeared to seek a compromise after the sentence was announced, calling on the authorities to show "mercy" to the women. The Church had previously declined to issue a public appeal for the women's release.

A White House spokesman called the sentence "disproportionate" and said the US had "serious concerns about the way these young women have been treated by the Russian judicial system". Police said they made "over 50 arrests" as protests took place outside the court after sentencing. A possible diplomatic incident arose after police chased a protester into the nearby Turkish embassy.

Defence lawyers for Nadezhda Tolokonnikova, 22, Maria Alyokhina, 24, and Yekaterina Samutsevich, 30, had said the performance was not anti-religion and was a response to Orthodox Church support for Vladimir Putin ahead of the March presidential polls. The protest in the Christ the Savior Cathedral, where Russia's leaders traditionally celebrate religious holidays, came amid the largest anti-government demonstrations in modern Russia's history.

A host of Western and Russian celebrities had spoken out in support of the group in recent weeks, including ex-Beatle Paul McCartney and US pop diva Madonna. High-profile figures from Russia's arts world had also signed a letter calling for the women to be freed. The Kremlin's own human rights council also called for their release and Amnesty International named them prisoners of conscience in April.

Putin said earlier this month he hoped the court would not judge the women "too harshly", a comment that sparked a wide range of interpretations. The maximum possible sentence for the charges was seven years. Prosecutors had asked for three years for each of the defendants, two of whom have small children they have not seen since their arrests in March.

The three women were kept behind a glass screen for the duration of the trial at the reading of Friday's verdict, which attracted massive international media attention. Hundreds of the group's supporters, many wearing their trademark coloured balaclavas, chanted "Free Pussy Riot!" and "Down with the police state!" in the street outside as the court session began. Putin has not commented on Friday's ruling.