MOSCOW

Russia's deputy foreign minister said on Monday that Finland and Sweden will not strengthen their security by joining NATO.

On the contrary, the general level of tension in Europe will increase, Sergey Ryabkov told reporters in Moscow.

"They should have no illusions that we will just put up with this ... in Brussels, in Washington, and in other NATO capitals ... the overall level of military tension will increase, and there will be less predictability in this area," Ryabkov said.

Asked about any possible steps Russia may take in response, the diplomat said moves will depend on "a practical outcome" of Finland and Sweden's admission to the military alliance.

Ryabkov expressed regret that "common sense is being given up to some phantom ideas" about what should be done in the current situation, meaning the Russia-Ukraine war, which began in February.

"This is another grave mistake with far-reaching consequences. But what to do, such is the level of those who make political decisions in the respective countries today," he said.

The leaders of Finland and Sweden have confirmed their intention to join NATO, abandoning decades of military non-alignment. The membership needs to be approved by all 30 members of the alliance.

Addressing NATO foreign ministers in Berlin on Sunday, NATO chief Jens Stoltenberg said Sweden and Finland are NATO's closest partners and if they decide to apply for membership, it would be “historic.”

“Their membership in NATO would increase our shared security, demonstrate that NATO's door is open and that aggression does not pay,” Stoltenberg said, reiterating that all sovereign nations have the right to choose their own path.