This week, Putin said that the two Nordic countries could join NATO if they wanted to.
He told the countries not to host NATO infrastructure.
If NATO military contingents were to deploy in the nations, Russia would respond in kind.
Russia would respond in kind if either Sweden or Finland hosted NATO's military forces or infrastructure.
Putin made the comments to Russian state media while talking about NATO's formal invitation to the two countries.
We don't have the same problems with Sweden and Finns. Putin told Russian state media that they wanted to join NATO.
If military contingents and infrastructure are deployed there, we will have to respond in kind and create the same threats for the territories from which threats towards us are created, he said.
Russia's relationship with both countries would be subject to some new Tensions if they joined the alliance, according to Putin.
Putin said that everything was fine between them, but now there might be some tension. If there is a threat to us, it is inevitable.
After warnings from Russia about joining NATO, Putin made a new comment. Russia threatened to restore military balance in the Baltic states if it was forced to do so.
Turkey has dropped its objections to the countries joining the alliance. Turkey, Finland, and Sweden have all agreed to allow the membership process to proceed, signaling an end to the two countries' neutrality in Europe.
Business Insider has an article on it.