The United States and France have welcomed a move by Finland and Sweden to apply for a NATO membership.

White House Press Secretary Karine Jean-Pierre expressed US support for the two countries' decision at a news conference on Monday. She said Finland and Sweden are close and valued defense partners of the US and NATO.

Pentagon Press Secretary John Kirby also spoke about the issue in a news conference on Monday. He said, "NATO is a defensive alliance. It has never, and does not now pose a threat to any other nation, and that includes Russia." He added, "It's not up to Mr Putin or any other third party to get a veto on whether a nation joins NATO or not."

He went on to say, "I think we need to remember who is actually the aggressor here, and whose actions probably are motivating those two nations to want to join NATO. That's Mr Putin and Russia themselves."

France's presidential office said in a statement on Monday that French President Emmanuel Macron "welcomes and supports these decisions coming from two very close European partners."

The statement says the two countries joining NATO will reinforce the security and stability of the Baltic Sea region as well as that of Europe as a whole, and of the Euro-Atlantic area."

It also says France is ready to increase its security and defense cooperation with the two nations, including through high-level political consultations and enhanced military interactions.

France apparently is sending a warning to Russia, saying, "Whoever would seek to test European solidarity by threatening or attacking their sovereignty through whatever means, must be certain that France will stand shoulder to shoulder with Finland and Sweden."