Former Russian president Dmitry Medvedev, a close ally of Vladimir Putin, has warned if Finland and Sweden decide to join Nato, Russia will deploy nuclear weapons to the Baltic States and Scandinavia.
In a message on Telegram, Medvedev, deputy chairman of Russia's security council and president from 2008 to 2012, said if Sweden and Finland drop their neutral status and join Nato, this would more than double Russia's land border with Nato members.
"Naturally, we will have to reinforce these borders," he said.
"In this case, it would not be possible to talk any more about the Baltic non-nuclear status. The balance has to be restored," he added.
Medvedev said Russia would "seriously reinforce its group of ground forces and air defences and deploy significant naval forces in the Gulf of Finland".