(Adds quote, detail, background, reaction from Norway)
By Tom Balmforth and Victoria Klesty
MOSCOW/OSLO, Oct 24 (Reuters) - A Russian commission on Thursday recommended President Vladimir Putin pardon a Norwegian man jailed for spying, spurring hopes in Norway that he may be released as part of a spy swap brokered behind closed doors.
Frode Berg, a retired guard on the Norwegian-Russian border, was detained in December 2017 and jailed for 14 years after being convicted of gathering intelligence about nuclear submarines. He pleaded not guilty to charges of espionage on behalf of Norway.
According to an unconfirmed Lithuanian Baltic News Service report earlier this month, Russia and Lithuania are negotiating a spy exchange that will secure the return of several captured agents, including a Norwegian national, to their home countries.
The Kremlin has declined to comment, but the report spurred speculation Berg would be released. Russia and Norway's foreign ministers are due to meet in Berg's hometown of Kirkenes on Friday.
On Thursday, an official Moscow commission that deals with prison pardons said it had recommended Berg be pardoned, something that is usually decided by Russia's president.
"Berg's request has been examined, a pardon was recommended. The documents have been sent to the presidential administration," Tatyana Potyaeva, a member of the commission, was quoted as saying.
"We interpret this as yet another confirmation that what has been said out of Vilnius over the last week is correct, and that there really is a three-way deal between Russia, Lithuania, and Norway, and that Frode Berg is part of this exchange," Berg's Norwegian lawyer Brynjulf Risnes told Reuters.
In snowy Kirkenes, inhabitants have campaigned to highlight Berg's plight. A banner in the centre of town displays a picture of Frode Berg with the words "Help Frode home!"
"Things are moving in this case. It is very positive for Frode and his family," Rune Rafaelsen, the mayor of Soer-Varanger municipality, which includes Kirkenes, told Reuters.
Shortly before the Moscow commission's announcement, Russia issued a statement saying it was concerned by Norwegian military spending and the development of military infrastructure there, something it said clearly targeted Moscow.
"Military infrastructure is being modernised, new weapons are being bought. The plans to develop the armed forces are clearly anti-Russian," Russia's foreign ministry said in a statement. "Such a situation can only alarm us..."
Foreign Minister Sergei Lavrov plans to raise those concerns on Friday at talks with his Norwegian counterpart in Kirkenes, the ministry added. (Additional reporting by Maria Kiselyova in Moscow and Gwladys Fouche in Kirkenes; writing by Tom Balmforth; editing by Larry King)