The EU condemned Russia on Friday for barring entry to European lawmaker Rebecca Harms, who flew to Moscow to observe the trial of a Ukrainian female pilot Nadia Savchenko accused of espionage.

Harms, a German MEP who co-chairs the Greens group in the European Parliament, said she was refused entry on Thursday despite holding a diplomatic passport.

"We condemn the refusal, at a Moscow airport, to allow MEP Rebecca Harms to enter the territory of the Russian Federation, despite her having checked with the Russian authorities before traveling," a spokesman from the EU diplomatic service told Interfax-Ukraine on Friday.

Harms was on her way to see the trial of Ukrainian pilot Nadia Savchenko, Ukraine's only female aviator of a Su-24 bomber who is currently being held in a Russian jail, and "whose continued detention remains a matter of concern for the EU," the spokesman added.

Russia's "lack of transparency" over its list of people blacklisted from entering the country was "regrettable" and went against the spirit of the visa agreement between Brussels and Moscow, the spokesman said.