Russian President; Vladimir V. Putin kept the world in suspense during his meeting with French President Emmanuel Macron on Monday.

Putin said he was prepared to keep negotiating over Russia’s security demands in Eastern Europe but offered a stark warning over the possibility of a full-scale war between Russia and the West — using a five-hour meeting with his French counterpart to keep the world guessing about his intentions.

The proposals made by President Emmanuel Macron of France in their one-on-one meeting at the Kremlin were “too early to speak about” but could create “a foundation for our further steps,” says Mr. Putin.

Mr. Macron, in a joint news conference with Mr. Putin after their hastily scheduled meeting, described the coming days as potentially decisive in heading off what the West fears could be a Russian invasion of Ukraine.

“We are in a situation of extreme tension, a degree of incandescence that Europe has rarely known in the past decades,” Mr. Macron said.

The meeting came as President Biden hosted Chancellor Olaf Scholz of Germany at the White House to coordinate a trans-Atlantic response to a potential attack on Ukraine, underscoring the intense unease in the West touched off by Mr. Putin’s enormous troop buildup around Ukraine’s borders.

Mr. Biden said on Monday that Western countries would take a “united” approach to rising tensions between Russia and Ukraine, and he vowed that a controversial gas pipeline project designed to send gas from Russia to Germany would not go forward in the event of a military invasion.

Mr. Putin appeared to relish the attention — and signaled he was prepared to draw out the mystery around his next moves that have turned the Russian troop buildup into the West’s most urgent crisis.

According to the New York times, Putin is an avid geopolitical tactician, and Monday’s concurrent talks in Moscow and Washington showcased his ability to force the West to pay attention to the Kremlin’s longstanding grievances over NATO’s expansion to Russia’s borders. But whether that attention will be enough to satisfy Mr. Putin is far from clear.

Some analysts worry that his engagement in diplomacy in recent weeks is merely buying time for Russia’s military to make final preparations for an invasion.

Mr. Putin said Russia was still working on a new written response in its back-and-forth with NATO and the United States over the security architecture of Eastern Europe, predicting that the “dialogue” would continue even though he said the West had ignored Russia’s principal demands.
He told reporters at the Kremlin that if Ukraine were to join NATO — a scenario that Western officials characterize as a far-off possibility, but one that the Kremlin describes as an existential threat — a wider war would follow.

“Do you want France to go to war with Russia?” Mr. Putin said in answering a French reporter’s question, claiming that a NATO-allied Ukraine would seek to retake Crimea, the Ukrainian peninsula that Russia annexed in 2014. “That’s what will happen!”

Mr. Putin saved his greatest ire for President Volodymyr Zelensky of Ukraine. Asked whether Russia would invade Ukraine, Mr. Putin did not rule out the possibility. He insisted Mr. Zelensky needed to implement the peace plan negotiated in Minsk, Belarus, in 2015 — one that could give the Kremlin a way to influence Ukraine’s foreign-policy decisions.

“You may like it, you may not like it — deal with it, my gorgeous,” Mr. Putin said of Mr. Zelensky, repeating a crude Russian rhyme.

Mr. Macron was scheduled to fly to Kyiv, the Ukrainian capital, on Tuesday to continue his shuttle diplomacy in a meeting with Mr. Zelensky. The French president has emerged as Europe’s main interlocutor with Mr. Putin in the crisis; the two have spoken on the phone five times since December, and Mr. Putin said they would speak again after Mr. Macron’s visit to Ukraine.

The two presidents’ meeting Monday evening was unusual both for its duration and its format — the men spoke one-on-one, without aides in the room. They held a joint news conference that began at about midnight Moscow time.

Mr. Macron said he had coordinated closely with the Western allies, including the United States and Germany. But some supporters of Ukraine’s pro-Western course have criticized him for being too solicitous of Mr. Putin’s demands. Mr. Macron did nothing to assuage those concerns by telling reporters before he met with Mr. Putin that a “Finlandization” of Ukraine was “one of the models on the table.”

The term alludes to how Finland, facing the Soviet Union during the Cold War, was able to maintain independence from its powerful neighbor and survive as a democracy on condition of strict neutrality. A “Finlandization” of Ukraine would imply that it would never join NATO and that Russia would exercise considerable influence over its political options.

Mr. Macron did not address the model in the news conference after Monday’s meeting, but he emphasized his belief that Russia’s concerns could be addressed without compromising core Western principles.

“Russia is European,” Mr. Macron said. “Whoever believes in Europe must know how to work with Russia and find the ways and the means to construct the European future among Europeans.”

Mr. Macron said both the West and Russia needed to get over the traumas of the past and build “useful solutions.” He said the “first priority” of his visit was to secure military stability and avert war “in the short term.” Discussions could then continue to build “medium-term solutions.”

“Can NATO solve the whole question of our collective security?” Mr. Macron said. “I don’t believe so.”

The French president offered few details of his ideas, but said they would involve rethinking post-Cold War security arrangements because “there is no security for Europeans if there is not security for Russia.”