Russian Deputy Foreign Minister Sergey Ryabkov has said joining NATO would be a mistake for Finland and Sweden.
In an interview with RIA Novosti, he warned of grave consequences if the countries succeed in their NATO bid.
According to him, the security of both countries will not be strengthened after they join the Alliance.
"No one should have the illusion that Russia will reconcile with the situation," he said. "Moscow's reaction will depend on the concrete steps taken by Stockholm and Helsinki," he said.