German Foreign Minister Guido Westerwelle said on Monday he was "very concerned" over a Russian court verdict that found billionaire Mikhail Khodorkovsky guilty of charges of oil theft, dpa reported.
"The circumstances of the case are extremely questionable and a setback on the country's path towards modernization," Westerwelle said in a statement.
"It is in the interest of our Russian partners to take these worries seriously and campaign consistently for the rule of law, democracy and human rights," the foreign minister warned.
Earlier, a spokesman for Chancellor Angela Merkel responded cautiously to the guilty verdict, and said the case could only be judged once the full verdict and sentence was known, including the court's justification.
The press was ordered out of the Moscow courtroom after Khodorkovsky and co-defendant Platon Lebedev were found guilty, but before Judge Viktor Danilkin began reading out the lengthy ruling.
German government spokesman Christoph Steegmans said the trial was being watched very closely, as it "put to the test" judicial principles in Russia.
However, German Human Rights Commissioner Markus Loening earlier called the judgement "an example of arbitrary political justice."
"I am very outraged at the guilty verdict," Loening told German Press Agency dpa. "The judgement throws no good light on circumstances in Russia."
The verdict showed that "President Dmitry Medvedev's rhetoric about the rule of law is exactly that - mere rhetoric," the commissioner added.
"The judgement is a crass misinterpretation of what happened in court," Loening said. He had attended parts of the trial and said witness testimonies did not support the allegations against Khodorkovsky.
"To the contrary - testimonies by the former Russian prime minister Mikhail Kasyanov and former economics minister German Gref clearly showed that the allegations against Khodorkovsky are wrong," Loening said.
Human rights organization Amnesty International called for an independent review of the charges against Khodorkovsky.
"The judgement and the entire trial show how far Russia is from the rule of law. Might stands above the law," said Amnesty's Russian affairs expert Peter Franck.
He said the trial was unfair, the defence was obstructed and that witnesses for the defence were not heard in court.
"Russia needs to finally implement the standards of the European Convention on Human Rights," Franck demanded. He also criticized political interference in the trial.
"Public prejudgements of Khodorkovsky, as expressed by Prime Minister Vladimir Putin, are a clear influence of justice," Franck said.
That was a reference to remarks by Putin earlier this month, when the prime minister declared - before the verdict was delivered - of Khodorkovsky, "the thief must remain in jail."
Lawyers for the 47-year-old said they would appeal against the verdict. The case drew major international attention, as a test of the independence of the Russian justice system and the country's adherence to constitutional law.
Human rights commissioner Loening said the European Union should consider measures such as an entry ban for the Russian lawyers and judges "who bend the law to such a degree."
"It will be important to support those in Russia who campaign for freedom and democracy," Loening added.