Madonna has used a performance in Moscow to rail against the trial of Russian punk band Pussy Riot, calling it a "tragedy".
The three members of the band, Maria Alyokhina, Nadezhda Tolokonnikova and Yekaterina Samutsevich stormed the altar of Moscow's Christ the Saviour cathedral in February to perform a "punk prayer" calling on the Virgin Mary to rid the country of then prime minister Vladimir Putin, who is now Russia's president.
The trial of the members for "religious hatred", which is closing this week, has attracted attention from pop and rock stars around the world, including Sting, Red Hot Chilli Peppers, Jarvis Cocker and Johnny Marr.
Madonna, opening her new fitness centre in Moscow, has drawn attention to the plight of Pussy Riot
Madonna, who was in Moscow to give a concert and launch her own fitness club, weighed into the debate, which has divided the country.
She told Reuters: "I am against censorship and throughout my whole career I've always promoted freedom of expression, freedom of speech. So obviously, I think that what happened to them (Pussy Riot) is unfair.
"I hope they do not have to serve seven years in jail. That would be a tragedy.
"I think art should be political. Historically speaking, art always reflects what's going on socially.
So for me, it's hard to separate the idea of being an artist and being political."
Pussy Riot members Nadezhda Tolokonnikova, Yekaterina Samutsevich and Maria Alekhina
On Tuesday, state prosecutor Alexei Nikiforov requested three years' prison for the women, saying in closing arguments that they had "set themselves up against the Orthodox Christian world.
"The actions of the accomplices clearly show religious hatred and enmity. Using swear words in a church is an abuse of God."
One of Russia's most prominent prisoners, former oil tycoon Mikhail Khordorkovsky, has likened the trial to a medieval inquisition.
The businessman said in a statement on his website: "It’s painful to follow events in Moscow’s Khamovnichesky court where Masha, Katya and Nadya are being tried.
A woman wears a T-shirt with Putin's picture and the inscription: "A very dangerous criminal wanted. Reward: A free Russia" and holds a poster that reads: "This is not the court, this is a lynching!"
“The word ‘tried’ can be used here only in the sense in which it was used by medieval inquisitors.The mistakes of radicalism can be excused by youth.
"I call on all thinking, educated and simply good and kind people to send words of hope to the girls.”
He said the girls would be locked in a glass cage in the courtroom for 11 hours a day, with only instant noodles to eat, and would only have three hours sleep in their cells at night.
The UK's shadow Foreign Minister Kerry McCarthy has been in court in Moscow, following the punk band's trial and tweeting her reactions.