* Madonna hopes Pussy Riot trio will not be jailed
* Jailed oil tycoon wants leniency despite "mistakes"
* Opposition says Putin is trying to silence dissenters
By Alissa de Carbonnel and Kiryl Sukhotski
MOSCOW, Aug 6 Pop singer Madonna urged Russia on Monday not to jail three women from the punk band Pussy Riot for staging a protest in a church, while jailed former oil tycoon Mikhail Khodorkovsky likened their trial to a medieval inquisition.
Maria Alyokhina, 24, Nadezhda Tolokonnikova, 22, and Yekaterina Samutsevich, 29, face up to seven years in jail for storming the altar of Moscow's main cathedral on Feb. 21 and belting out a "punk prayer" calling on the Virgin Mary to rid Russia of Vladimir Putin, the prime minister who has since returned to the presidency.
Madonna weighed into a trial which the opposition says is part of a wider crackdown on dissent by Putin after the biggest protests since he rose to power in 2000.
In Moscow to give a concert and open a branch of her own fitness club, the American singer, songwriter, entrepreneur and actor added her voice to other international singers such as Sting and Red Hot Chili Peppers who have appealed for leniency.
"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," Madonna, whose songs include 'Like a Virgin' and 'Like a Prayer' and have also courted controversy, told Reuters Television.
"I hope they do not have to serve seven years in jail. That would be a tragedy," she said. "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."
The band's stunt infuriated church leaders and the Kremlin and upset many Orthodox Christian believers for whom the Christ the Saviour Cathedral is a sacred place of worship and its pulpit a place reserved exclusively for priests.
Accused of hooliganism motivated by religious hatred, the three woman on trial said they wanted their performance to be considered as a political act directed against the church merging with state security services.
"There is a big difference between criticism and hatred. Protest is not hatred and it is not violence," Alyokhina told the court on Monday.
GROWING SUPPORT FOR PUNKS
Russian prisoner Khodorkovsky, who was tried in the same Moscow courtroom as the women, said the Pussy Riot trio may have gone too far by protesting on an altar but called for leniency because of their age.
"It's painful to follow events in Moscow's Khamovnichesky court where Masha, Katya and Nadya are being tried," Khodorkovsky said in a statement on his website. "The word 'tried' can be used here only in the sense in which it was used by medieval inquisitors."
Khodorkovsky, 49, former head of oil company Yukos who was jailed in 2004 on fraud and tax evasion charges, said: "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."
Drawing on his own experiences, Khodorkovsky, unpopular among many Russians who see him as one of the country's "robber-barons", said defendants in such a high-profile case were woken before breakfast and shuttled to court at the crack of dawn.
During an 11-hour day locked in a glass and metal courtroom cage known as "the aquarium", he said instant noodles were the only food served.
"I know what the aquarium in courtroom number seven is. They made it specially for us," Khodorkovsky said, referring to the second of his two trials. "You feel like a tropical fish. It's hot. The air conditioning doesn't circulate through the glass."
After the court session, he said the women would arrive back at their cells after dinner and probably only have time to sleep for about three hours. The only time to shower was on Saturday.
"I don't know how the girls can endure it. The judge of course knows about this regime. Is this torture?," he said.
There is known to be a personal enmity between Putin and the jailed oligarch and Putin's critics regard Khodorkovsky as a political prisoner and hold up his case as an example of the Kremlin's ability to influence the judiciary.
But it is the Pussy Riot trial that is being seen as the latest test of his tolerance. Critics have held up a tough new law that tightens control over foreign-funded lobby groups as evidence of that, along with stricter Internet rules and a big rise in fines for protesters.