Russian President Vladimir Putin warned his Finnish counterpart Saturday that relations between the two neighbors could be "negatively affected" if Finland follows through with plans to apply for NATO membership.
The Kremlin's press service said in a statement that Putin told Sauli Niinisto Finland's abandonment "of its traditional policy of military neutrality would be an error since there are no threats to Finland's security."
"Such a change in the country's foreign policy could negatively affect Russian-Finnish relations, which had been built in the spirit of good neighborliness and partnership for many years, and were mutually beneficial," the statement added.
The response came after Niinisto told Putin in a phone conversation that the militarily non-aligned Nordic country, which has a complex history with its huge eastern neighbor, "will decide to apply for NATO membership in the coming days."
Niinisto's office said in a statement that the Finnish head of state told Putin how starkly Finland's security environment had changed after Moscow's Feb. 24 invasion of Ukraine, and pointed to Russia's demands for Finland to refrain from seeking membership of the 30-nation Western military alliance.
"The discussion (with Putin) was straightforward and unambiguous and was held without exaggeration. Avoiding tensions was considered important," said Niinisto, Finland's president since 2012 and one of a handful of Western leaders who has been in regular dialogue with Putin over the past decade.
Niinisto pointed out that he had already told Putin at their first meeting in 2012 that "each independent nation would maximize its own security."
"That is still the case. By joining NATO, Finland will strengthen its own security and assume its responsibilities," Niinisto said.
Niinisto stressed that Finland, despite its likely future membership in NATO, wants to continue to deal with Russia bilaterally in "practical issues generated by the border neighborhood" and hopes to engage with Moscow "in a professional manner."
According to the Kremlin statement, the two leaders also discussed Russia's "military operation" in Ukraine, and the possibility of achieving a political solution. Putin said negotiations between Moscow and Kyiv had been suspended due to Ukraine's "lack of interest in a serious and constructive dialogue."
The phone call was conducted on Finland's initiative, Niinisto's office said.
Finland shares a 830-mile border with Russia, the longest by any European Union member.
Niinisto and Finnish Prime Minister Sanna Marin on Thursday jointly endorsed their country's NATO bid and recommended that Finland "must apply for NATO membership without delay" to guarantee its security.
A formal announcement from Niinisto and Marin of Finland's intention to apply for NATO membership is expected on Sunday. Marin's governing Social Democratic Party approved the membership bid on Saturday, paving way for a parliamentary vote next week to endorse the move. It's expected to pass with overwhelming support. A formal membership application would then be submitted to NATO headquarters in Brussels.
Neighboring Sweden is set to decide on its NATO stance on Sunday at a meeting of the governing Social Democratic Party led by Prime Minister Magdalena Andersson.
One possible hurdle to Finland and Sweden joining the alliance came from NATO member Turkey, whose president said Friday he was "not favorable" to the idea.
Recep Tayyip Erdogan cited support in Sweden and other Scandinavian countries for Kurdish militants — whom Turkey considers to be terrorists.
Finland's Foreign Minister Pekka Haavisto said Saturday that he had already called his Turkish counterpart, Mevlut Cavusoglu, "to take the tensions down."
"I'm sure that we will find a solution to this item as well," he told reporters at the start of an informal NATO foreign ministers' meeting in Berlin late Saturday.
U.S. President Joe Biden held a joint call Friday with both Niinisto and Andersson where, according to a White House statement, he "underscored his support for NATO's Open Door policy and for the right of Finland and Sweden to decide their own future, foreign policy and security arrangements."
Additional reporting by the Associated Press.