The alliance firmed up its plans to include Ukraine eventually, but gave no timetable, siding with President Biden and frustrating some East European members.
NATO declared on Tuesday that Ukraine would be invited to join the alliance, but did not say how or when, disappointing its president but reflecting the resolve by President Biden and other leaders not to be drawn directly into Ukraine’s war with Russia.
In a communiqué agreed to by all 31 NATO nations, the alliance said that “Ukraine’s future is in NATO,” and it will be allowed to join when the member countries agree that conditions are ripe — but it did not offer specifics or a timetable. It promised to continue supporting Ukraine in its fight against Russia and to engage the alliance’s foreign ministers in a periodic review of Ukraine’s progress toward reaching NATO standards — in both democratization and military integration.
The wording means that Mr. Biden, who declared last week that “Ukraine isn’t ready for NATO membership,” and like-minded allies had prevailed over Poland and Baltic nations that wanted a formal invitation for Ukraine to join the alliance as soon as the war ends. NATO leaders released the document, a compromise product after weeks of argument, at a summit meeting in Vilnius, Lithuania.
Hours earlier, President Volodymyr Zelensky of Ukraine, apparently aware of what it would say, issued a blast at the NATO leadership. “It’s unprecedented and absurd when a time frame is not set, neither for the invitation nor for Ukraine’s membership,” he wrote on Twitter before landing in Vilnius.
The NATO commitment went somewhat beyond its vague statement in 2008 that Georgia and Ukraine would eventually become members. Given Ukraine’s shaky democracy, corruption and old Soviet arsenal, that was a hazy prospect at best, and neither it nor Georgia has since joined.
In lieu of membership, NATO leaders on Tuesday offered Mr. Zelensky new military aid to fight Russia, promises of further integration and statements intended to declare to President Vladimir V. Putin that his strategy of wearing down the European nations would not work. Their communiqué stated that Ukraine had moved closer to the alliance’s political and military standards.
Mr. Zelensky will have dinner with NATO leaders and participate on Wednesday in the first NATO-Ukraine Council, an effort to integrate the country into the alliance’s discussions even as a nonvoting member.
But what Ukraine wants — and what Mr. Biden and Germany, among others, are reluctant to offer — is the main benefit of full membership: The promise of collective defense, that an attack on any single NATO country is an attack on all.
Mr. Biden has warned that he does not want to be forced into direct combat with Russian forces, warning “that is World War III.”
Mr. Zelensky had threatened not to attend the meeting if he was unhappy with the NATO commitment. He and his top aides have argued that if Ukraine had entered NATO, Mr. Putin might not have dared invade and risk a war with the Western alliance.
Historians and geostrategists will be arguing about that what-if for years. But with the release of the communiqué, Mr. Biden appears to have gotten two of the things he wanted most from this summit.
With Swedish concessions and help from Jens Stoltenberg, NATO’s secretary general, Mr. Biden helped persuade President Recep Tayyip Erdogan of Turkey to drop his blockade of Sweden’s membership, which requires unanimous consent. And with the language adopted on Tuesday in Vilnius, there is still no defined date — or even defined conditions — under which Ukraine will become a member.
The closest the statement comes to a commitment are these words: “We will be in a position to extend an invitation to Ukraine to join the alliance when allies agree and conditions are met.”
As one significant concession, NATO agreed that Ukraine would not need to go through a preliminary process to prepare it for an invitation. Both Sweden and Finland, which joined this year, were also allowed to skip such a process.
Moscow made clear that it was closely following the summit. Dmitri S. Peskov, the Kremlin spokesman, said that new weapons provided to Ukraine would “force us to take countermeasures,” and criticized Turkey for allowing Sweden to join. Foreign Minister Sergey V. Lavrov said that Russia would examine “how quickly and how deeply NATO expands on the territory of Finland and Sweden,” and would respond accordingly.
The dispute within NATO over its joint statement had deep roots, said Samuel Charap, senior political scientist at the RAND Corporation.
“There is a fundamental divide between the United States, Germany and other less vocal allies who are committed to the principle of the open door to NATO, but without wanting to see a concrete timeline or automaticity, and those countries near Russia who are pushing very hard to turn the vagueness of Bucharest into something much more concrete,” he said. It was a 2008 NATO summit in Bucharest, Romania, that promised Ukraine and George eventual membership.
For the United States, Mr. Charap said, membership of Ukraine too soon “involves the risk of a NATO-Russia war arising from a country at war with Russia entering the alliance,” he said, noting that Moscow has for many years called Ukrainian membership in NATO a red line. “For the others, Ukrainian membership is a path to peace and stability, because it will deter Russia and anchors Ukraine and ends the instability.”
The Bucharest promise was a way to kick the can of Ukrainian membership down the road. That may no longer be possible, given the war. “At some point the road comes to an end, and we might be reaching that end,” Mr. Charap said.
The NATO alliance has been eager to use this Vilnius summit as a display of trans-Atlantic unity, and in that goal it largely succeeded. Secretary of State Antony J. Blinken said in several interviews that Mr. Putin’s strategy has been to wait for NATO nations to tire of the war. But the Russian leader, he said is “not going to outlast Ukraine, and the sooner he ends this war of aggression, the better.”
The allies came to Vilnius with more pledges of weapons and military equipment for Ukraine to bolster its slow-moving counteroffensive: long-range “Scalp” cruise missiles from France; 25 more Leopard tanks, 40 additional infantry fighting vehicles, and two more Patriot air-defense missile launchers. There was a $770 million package from Germany and $240 million from Norway for unspecified equipment and other support.
Additionally, the defense ministers of Denmark and the Netherlands announced they had gathered 11 countries to help train Ukrainian pilots on F-16 fighter jets as soon as next month. Mr. Biden agreed in May to drop his objections to giving Ukraine F-16’s, though that may not happen until next year.
The Scalp missiles are the same weapon as the Storm Shadows that Britain, in May, said it had sent to Ukraine. The missiles, jointly manufactured by France and Britain, have a range of about 150 miles.
France had previously ruled out providing Ukraine with such missiles over concerns they could be used to attack targets in Russia, escalating the conflict. But President Emmanuel Macron said he was sending Scalp missiles now to help Ukraine defend itself.
The communiqué also had more than 60 references to nuclear weapons, warning Russia of “severe consequences” if it uses onein the war, while promising to modernize the nuclear forces of NATO’s three nuclear powers: the United States, Britain and France.
Kremlin officials have suggested several times that Russia could use nuclear weapons in Ukraine, and it recently began to deploy them in Belarus. “We condemn Russia’s irresponsible nuclear rhetoric and coercive nuclear signaling,” the leaders’ statement said.
The communiqué also has long sections on the threats posed by China. While its wording is milder than its references to Russia, it argues that China presents a longer-term danger. The language is significant because in past years, NATO, focused on European security, barely thought about China.
“The P.R.C. seeks to control key technological and industrial sectors, critical infrastructure, and strategic materials and supply chains,” it said, using the abbreviation for People’s Republic of China. “It uses its economic leverage to create strategic dependencies and enhance its influence. It strives to subvert the rules-based international order, including in the space, cyber and maritime domains.”
Taken together, the Russia and China sections of the communiqué leave little doubt that NATO sees the world heading into an era of confrontation at least as complex as the Cold War.
Mr. Stoltenberg was at pains to try to show reporters that NATO’s commitment to Ukrainian membership was different from the vague promise of 2008.
He said NATO had drawn much closer to Ukraine since Russia seized Crimea and fomented a separatist war in eastern Ukraine in 2014, and NATO began to train Ukrainian troops. They have moved closer still since Russia’s full-scale invasion last year, when NATO countries began to pour tens of billions of dollars worth of military equipment into Ukraine.
Mr. Stoltenberg and American officials argue that Mr. Zelensky will be able to return to Ukraine with some major prizes: direct involvement in NATO discussion of the war, a firmer commitment to Ukrainian membership, new commitments of military and financial aid for the medium and longer term, and the message of resolve that sends to Mr. Putin.