Finland joining NATO a threat to Russia, says Kremlin

Russia would see Finland's accession to the NATO military alliance as a threat and the move would not contribute to more security, Kremlin spokesman Dmitry Peskov said on Thursday, media reports said.

"As we have said many times before, NATO expansion does not make the world more stable and secure," Peskov told reporters after Finland's top politicians announced their support for an application for NATO membership, CNN reported.

Peskov added that Russia's reaction will depend on the development of the NATO military infrastructure.

"It will depend on what this expansion process will entail, how far and how close to our borders the military infrastructure will move," Peskov said, CNN reported.

Russia will analyse the situation with Finland's entry to NATO and will work out the necessary measures to ensure its own security, he added.

Finland would be "warmly welcomed into NATO", said the military alliance's chief Jens Stoltenberg after the country's top politicians said they wanted to join.

"This is a sovereign decision by Finland, which NATO fully respects. Should Finland decide to apply, they would be warmly welcomed into NATO, and the accession process would be smooth and swift," said Stoltenberg, according to his office, CNN reported.

"Finland is one of NATO's closest partners, a mature democracy, a member of the European Union, and an important contributor to Euro-Atlantic security," he added.

Earlier on Thursday, Finnish President Sauli Niinisto and Finnish Prime Minister Sanna Marin issued a joint statement announcing their support for a Finnish application to join NATO.

Stoltenberg said he agreed with the analysis from Niinisto and Marin "that NATO membership would strengthen both NATO and Finland's security."