Spokesman Dmitry Peskov told reporters on November 6 that the Kremlin would review the request in line with normal procedures.

He did not give further details.

Berg, a retired former inspector on the Norwegian-Russian border, was detained in Moscow in December 2017 by the Federal Security Service (FSB) and accused of seeking classified information relating to Russian nuclear submarines.

In April, the 63-year-old was found guilty and sentenced to 14 years in prison after a trial held behind closed doors in Moscow.

Berg pleaded not guilty to charges of espionage on behalf of Norway.

During a visit to Norway on October 25, Russian Foreign Minister Sergei Lavrov said a decision “will come soon” on whether to pardon Berg.

If the Norwegian is pardoned, he would be allowed to return to Norway, Lavrov said.

Russia's relations with the West have deteriorated in recent years, highlighted by tensions over Moscow’s aggression toward Ukraine, its support for Syrian President Bashar al-Assad, interference in foreign nations’ elections, and other issues.

Based on reporting by Reuters and Interfax