BRUSSELS — Finland will launch an immediate debate on joining NATO, Finnish officials said on Wednesday, as the country reconsiders its longtime stance outside the Western military alliance following Russia’s invasion of Ukraine.
Marin spoke alongside Swedish Prime Minister Magdalena Andersson, who said Sweden was also reexamining its position outside NATO, after Russian President Vladimir Putin’s Ukraine offensive plunged Europe into its most serious security crisis since World War II.
The ministers spoke as the Finnish government released an official assessment Wednesday of how Russia’s invasion has changed its security environment, beginning a process that has been expected to culminate in a request to join NATO.
The assessment, known as a white paper, does not make a recommendation about NATO membership, officials said, but will be used as a starting point for parliamentary debate as the country weighs a historic shift in its defense position.
Finland and neighboring Sweden are officially nonaligned militarily, but Russia’s aggression has led to a dramatic shift in public sentiment. Wednesday’s white paper marks the start of the process for Finland, where support for joining NATO has jumped to 68 percent, according to a poll over the weekend.
Their potential accession would probably draw outrage from Putin, who has described NATO expansion as a threat to Russian security. Now, his brutal war there may bring the military alliance closer to his door.
Ivo Daalder, who served as U.S. ambassador to NATO from 2009 to 2013, said that Finland and Sweden’s inclusion in NATO would strengthen security across Europe, because the alliance’s mutual defense guarantee would act as an effective deterrent against any potential Russian attack on its northern European neighbors.
“More importantly, you would bring in two very serious, very capable militaries into the alliance, countries that are then required to help defend all of NATO,” he said.
Security experts say the two nations punch above their weight militarily. Both have long histories of working closely with NATO countries, training with NATO forces, and contributing troops to the NATO-led mission in Afghanistan and to the coalition against the Islamic State. Just before the Russian invasion of Ukraine, Finland finalized its purchase of 64 F-35 fighters.
The Biden administration has said relatively little publicly about membership for Finland and Sweden, perhaps trying to avoid provoking additional reaction from Russia, but it has emphasized NATO’s open-door policy. The question of expanding the alliance was discussed last week at a meeting of NATO foreign ministers in Brussels.
State Department spokesman Ned Price said the war in Ukraine had prompted concerns that Putin may have aims beyond Ukraine. Putin has cited Kyiv’s goal of someday joining NATO as a threat to Russian security.
“The reason we may be seeing additional interest in a defensive alliance is precisely because we’ve seen offensive operations and aggression on the part of the Russian Federation,” he told reporters Tuesday. “So if there is any cause of increased interest on the NATO alliance … at the core of that, I think it’s fair to say, is Vladimir Putin.”
Finnish Defense Minister Antti Kaikkonen, speaking to reporters in Helsinki following the paper’s release, said he hoped a decision would be made before the summer solstice in late June. He said Finland’s military capability would contribute to NATO security.
Finnish Foreign Minister Pekka Haavisto said he hoped Finland and Sweden could take any potential step toward membership on the same timetable, but said Stockholm would make its own decision.
Sweden’s ruling Social Democrats, who have traditionally opposed NATO membership, have also said they will be rethinking their position in the coming months. The exact timing is unclear.
NATO Secretary General Jens Stoltenberg said the two countries meet NATO standards when it comes to “political, democratic, civilian control over the security institutions and the armed forces.”
“There are no other countries that are closer to NATO,” Stoltenberg, a former Norwegian prime minister, told reporters in Brussels last week.
“They are some of our closest allies in Europe, and so I can’t imagine a situation where there would be tremendous resistance to this idea,” Julianne Smith, the U.S. ambassador to NATO, said last week.
Daalder said that once NATO extends a formal membership invitation, the accession process could take months, requiring each of the alliance’s 30 members to ratify changes to the founding NATO treaty. When Croatia and Albania joined in the late 2000s, it took 11 months, he said, though the process might move faster for Finland and Sweden.
As Helsinki and Stockholm weigh whether to make it official, key questions are whether and how they will be protected from potential Russian aggression in the period between expressing interest and actual membership, which could take months.
Russia has warned of “serious military-political consequences” and “retaliation” should the two countries join. Although Finnish leaders have mostly played down the threat, the country is preparing for possible responses from Russia, from serious to mostly symbolic, said Henri Vanhanen, a foreign policy expert and adviser to Finland’s National Coalition Party.
Vanhanen expects that NATO will find ways to “signal that Sweden and Finland are protected” in the interim, such as making a political commitment to ensuring safe accession or stepping up military cooperation in some way.
“If they give us the signal that we are welcome, it is in their interest that this happens as smoothly as possible,” he said. “It would be a huge blow to NATO if their open-door policy is undermined.”
Stoltenberg said last week he was “certain that the alliance will find ways to address concerns about the period between potential application and ratification,” but he declined to offer specifics on what is being discussed.
“I think it’s not helpful if I start to speculate in the public exactly how we will do that,” he said. “But I am confident that if they apply, we will sit down, and we will find a way to address that issue.”
U.S. officials have minimized the likelihood of any Russian attack on Finland or Sweden during their potential application periods, if they apply, or any NATO-style security guarantees, but have suggested that Washington would seek other ways to bolster the countries’ security ahead of their accession.
Even without NATO protection, Finland and Sweden should theoretically have some measure of collective security. Article 42.7 of the E.U. treaty states that if a member is a victim of armed aggression, other members must come to its aid.
Finland’s Marin and Sweden’s Andersson wrote a letter last month to European Council President Charles Michel drawing attention to “the heightened role of the E.U.’s solidarity and commitment to the mutual defense clause” in Europe’s new security environment.
In a meeting with the Swedish leader last month, German Chancellor Olaf Scholz said the country “can count” on the E.U. if Russia lashes out.
Ryan reported from Washington.
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