What is ‘Finlandization,’ a Status Proposed for Ukraine?

President Emmanuel Macron of France invoked a Cold War-era term on Monday, telling reporters on his flight to Moscow that “Finlandization” of Ukraine was “one of the models on the table” for defusing tensions with Russia.

On Tuesday, standing alongside President Volodymyr Zelensky of Ukraine in Kyiv, Macron denied making the remark, which appeared to put him at odds with not only the Ukrainians but also the United States. But the idea is once again being discussed in diplomatic circles.

The term refers to Finland’s strict neutrality during the Cold War, enshrined in a 1948 treaty with Moscow when tensions between the Soviet Union and the West were at a high. The treaty ensured Finland that unlike other countries in Eastern Europe, it would not face a Soviet invasion, but in return, it agreed to stay out of NATO and allowed the giant next door to exercise significant influence over its domestic and foreign policy.

Ukraine, formerly a part of the Soviet Union, has increasingly tilted toward the West, economically and politically, while resisting Russian influence. In 2008, NATO said it planned eventually for Ukraine to join the alliance, a popular idea within the country, though it has never actually applied for membership and NATO officials say it would not happen any time soon.

“Finlandization” would appear to rule out that possibility, and allow Moscow a heavy hand in Ukrainian affairs — concessions Kyiv and NATO have rejected as unacceptable.

“All of this goes against what Ukraine has been striving for,” said Anna Wieslander, director for Northern Europe at the Atlantic Council. “It would be a big shift from a long-term political aim of joining NATO and joining the EU, which is what they have wanted.”

The arrangement Mr. Macron appeared to suggest is “a way of solving a problem by making a decision over the head of the Ukrainians,” said Richard Whitman, an associate fellow at the policy analysis group Chatham House.

President Biden has said that nations must be free to choose their own alliances.

President Vladimir V. Putin of Russia has long maintained that Ukraine and Russia are effectively one country, with insoluble historic and cultural ties. In 2014, after mass protests forced out a pro-Russian Ukrainian president, Russia invaded and annexed Crimea, and supported a separatist war in eastern Ukraine that is still dragging on.

With Mr. Putin determined to expand his sphere of influence and undermine an independent Ukrainian government, and the West making it clear it would not go to war against Russia to defend Ukraine, some experts have argued that “Finlandization” is the best course Ukraine can take.

The Kremlin is acutely aware that Finland, once a neutral buffer state between the Soviets and NATO, has become far less neutral, tilting strongly toward the West since the Soviet Union collapsed.

“While it remains outside NATO to this day,” said James Nixey, the director of European Union-Russia relations at Chatham House, “Finland is completely compatible with NATO, and with Western security architecture, and is very much ‘on side’ as far as a unified concept of European security is concerned.”