A Russian court found retired Norwegian border guard Frode Berg guilty of espionage on Tuesday and handed him a 14-year jail sentence.
Berg was arrested in Moscow in late 2017 and accused of gathering information about Russian nuclear submarines on behalf of Norway's intelligence services.
The conviction could harm relations between Russia and its NATO-member neighbor.
Read more: Russian arrested in Norway for spying
Hoping for a pardon
Berg, who was tried behind closed doors, pleaded not guilty to the charges. While he has admitted to acting as a courier for Norwegian intelligence, he insists he believed he was only delivering money. The 63-year-old was well-known in the Russian-Norwegian border area, often participating in cultural and humanitarian exchange projects.
Berg's lawyer said his client would not appeal the verdict and plans to request a presidential pardon from Vladimir Putin.
"He expects his government to undertake diplomatic efforts," defense lawyer Ilya Novikov said. "We see no practical use in appealing."
Ahead of the trial, Novikov had warned that Berg may not survive a lengthy sentence in a Russian prison, adding that he hoped diplomatic efforts could secure his client's freedom.
Putin discussed the case in talks with Norwegian Prime Minister Erna Solberg in Saint Petersburg last week. When asked about the possibility of a pardon, the Russian president said: "We must wait for the court proceedings ... We will take a look at what we can do with this depending on the court's decision."
Although Russia and Norway generally share amicable ties, Moscow's annexation of Crimea from Ukraine in 2014 has increased tensions between the two.
nm/rc (AP, AFP, Reuters)