BRUSSELS: The European Union (EU) expressed mounting worry yesterday over the trial of Russian girl-band PUSSY RIOT, whose members face years behind bars for a church protest against Vladimir Putin.

In a case that has stirred Western pop stars including MADONNA and polarised the Russian Orthodox country, prosecutors have sought three years in jail for the three twenty-something members, two of whom are mothers.

Detained in March, they stand charged with hooliganism motivated by religious hatred after asking the Virgin Mary to oust Putin in a musical "punk prayer" ahead of his presidential election win.

One of the band's lawyers yesterday announced a plan to take the case to the European Court of Human Rights.

"The EU is concerned about the reported irregularities related to this case since the group members were arrested in March, in particular the grounds for and conditions of their pre-detention," said a spokesman for the top EU diplomat Catherine Ashton.

The official said the trial, in the same Moscow court where former Yukos oil chief Mikhail Khodorkovsky underwent a controversial trial for tax evasion in 2010, was "accelerated in a way that seems at variance with due process".

EU diplomats are attending the hearings and vowing to keep a close eye on its progress, the spokesman said. "We are also worried by the reports of increasing intimidation, with pressure put on lawyers, on journalists and on possible witnesses," he said.

"The EU calls on Russia to respect its international obligations, notably the right of fair trial."

The case has outraged many Russian Orthodox believers but it has also caused an international outcry and focused attention on a crackdown on dissent since Putin returned to the presidency for a six-year term on May 7.

"The actions of the accomplices clearly show religious hatred and enmity," federal prosecutor Alexei Nikiforov said in closing arguments. "There was real mockery and humiliation directed at the people in the church," he said. Nikiforov did not press the court for the maximum seven-year sentence. Putin said last week that Maria Alyokhina, 24, Nadezhda Tolokonnikova, 22, and Yekaterina Samutsevich, 29, had done "nothing good" but should not be judged too harshly.