Nordic and Baltic foreign ministers, meeting in Copenhagen on Thursday, called on Russia to immediately release an Estonian policeman who they say was "abducted" from his country and jailed for 15 years in a case that violated international law.
Eston Kohver was sentenced last month for espionage, in a case that undermined relations between the north European countries and Moscow, already soured by Russia's annexation of Crimea and support for Ukrainian rebels.
"Mr Kohver's abduction and subsequent illegal detention in Russia constitute a clear violation of international law," the ministers from Denmark, Estonia, Finland, Iceland, Latvia, Lithuanian, Norway and Sweden said in a joint statement.
They said two Ukrainians, jailed by a Russian court last month for "terrorist attacks" in Crimea, should also be released immediately.
They also called for a fair and legal trial for Nadezhda Savchenko, a Ukrainian pilot detained in Russia and accused of murder.
The Baltic states, formerly part of the Soviet Union, have large Russian minorities, prompting fears Moscow could meddle there on the pretext of protecting Russian speakers, as it did in Crimea.
Baltic governments find Russian television news channels watched by many Russian speakers particularly jarring, which they say espouse propaganda. The eight states have said before that they would support independent media to challenge that.
"Countering the aggressive disinformation and propaganda with support to capacity-building in free and independent media must remain a key priority," the ministers said.