Ukraine and its Eastern European allies want the invite to come soon, but Washington and Berlin are wary.

By Robbie Gramer and Jack Detsch

U.S. President Joe Biden announces the G-7 nations’ joint declaration for the support of Ukraine as Ukrainian President Volodymyr Zelensky looks on during a NATO summit in Vilnius, Lithuania, on July 12, 2023. SEAN GALLUP/GETTY IMAGES

JANUARY 30, 2024, 3:58 PM

Ukraine and some of its strongest supporters are pushing NATO to formally invite Kyiv to become a member of the military alliance during a major upcoming summit, but their efforts are facing significant behind-the-scenes pushback from the United States and Germany, according to a dozen current and former officials familiar with the matter.

Kyiv has backing from Eastern European countries already in the military alliance, including Poland and the Baltic states, which view extending NATO membership to Ukraine as the most effective and least costly way to blunt Russia’s irredentist ambitions in Eastern Europe. Yet other Western NATO officials, mostly notably in Washington and Berlin, believe that it’s too soon to kick-start the process of admitting Ukraine to NATO while the country is still fighting a war against Russia.

Both the United States and Germany are top donors of military and economic aid to Ukraine. Officials in both countries insist that Ukraine should join NATO eventually, but that now isn’t the time to start the process. They said they believe the immediate focus should be on continuing to supply Ukraine with weapons and munitions to keep up the fight against Russia in the near term.

The fierce debate that is playing out behind the scenes in Washington and Brussels is existential for Ukraine and will determine the future of Europe’s security landscape as NATO continues to adjust to the reality of Russian President Vladimir Putin’s territorial ambitions.

A Ukraine in NATO could deal a death blow to Putin’s neoimperialist ambitions to annex Ukraine and possibly even further encroach on European territories. Only Ukraine’s NATO membership, some officials believe, will finally convince Russia to pump the brakes on its invasion and end the war.

Among the most vocal backers of rush-ordering Ukraine’s NATO membership invitation is Anders Fogh Rasmussen, the former Danish prime minister and NATO Secretary-General Jens Stoltenberg’s predecessor. “Very often, I hear the argument that we cannot invite Ukraine to join NATO as long as the war is going on,” he said. “I think that’s an extremely dangerous argument to use, because that de facto provides Putin with a veto over NATO and gives him an incentive to continue hostilities in Ukraine indefinitely.”

Other proponents of this view believe that bringing Ukraine into NATO sooner rather than later will be cheaper in the long run than the current Western strategy of funneling arms and munitions to Ukraine in perpetuity while keeping NATO membership on the back burner. Ukraine can only halt a Russian invasion once it is brought into the alliance’s fold, they argue.

“Delays in moving toward membership are not only pricey for Ukraine, but are also expensive for the alliance,” said Kristjan Prikk, Estonia’s ambassador to Washington.

Letting Ukraine into NATO too soon, however, particularly as large swaths of its territory are still occupied by Russian forces, could trigger a full-scale NATO-Russia conflict, given the 31-member alliance’s bedrock collective defense clause that calls for all NATO countries to defend any one country that has been attacked. The prospect of a Russia-NATO conflict turning nuclear looms in the background of these debates.

So, too, does the upcoming U.S. presidential election, where incumbent President Joe Biden looks slated to face off again against former President Donald Trump. Trump, long a critic of NATO, hasn’t said much on the campaign trail about Ukraine’s NATO membership, but many officials and experts believe he wouldn’t work to admit Ukraine into the alliance if he were elected—pushing Ukraine’s hope for joining back at least four years.

The debate also comes as some allies have begun wavering on their commitments to Ukraine, with some populist leaders in Europe, including in Slovakia and Hungary, opposing continued efforts to fund Ukraine’s war against Russia’s invasion. And a massive tranche of U.S. military aid for Ukraine is still stalled in Washington due to a political impasse in Congress.

The question of Ukraine’s NATO membership is a top agenda item for Stoltenberg, who is visiting Washington for meetings with top Biden administration officials this week.

Speaking at a press conference alongside Stoltenberg, U.S. Secretary of State Antony Blinken said Ukraine “will become a member of NATO” but declined to give any specifics on the timeline of when that would happen, underscoring the debate over Ukraine’s membership that is brewing behind the scenes within the alliance.

As the Biden administration begins crafting the agenda for a pivotal July summit in Washington, where it will host the leaders of all 31 NATO members, the issue is exacerbating tensions between the pro-membership camp, represented by Poland and the Baltic states, and the wait-and-see camp, led by Washington and Berlin. France, which is mulling its own package of security guarantees for Ukraine separate from NATO membership, is seen as open to putting forward a formal invitation for Kyiv to become a NATO ally.

In a meeting at the State Department earlier this month between U.S. diplomats and European parliamentarians pushing for a Ukrainian invite to NATO, the U.S. diplomats urged the Europeans not to try to make Ukraine’s NATO membership an agenda item at the upcoming summit, fearing that it would bring these internal divisions into the limelight and potentially give Russia grounds to escalate its military assault in Ukraine in the short term, according to several people who attended the meeting.

But the European lawmakers, who came from several countries—including Great Britain, the Czech Republic, and Lithuania—pushed back, arguing that the best way for the United States to show leadership regarding Ukraine was to lead on membership.

“The U.S. has been telling allies, ‘look, don’t put this on the agenda,’” said Jim Townsend, a former U.S. Defense Department official for NATO policy. “They’re going to have to come up with something that is reassuring, and is something of substance for Ukraine, and is a signal to Russia that we’re not backing off.”

All of this echoes Biden’s controversial decision to push off Ukraine’s NATO membership bid at a major alliance summit last year in Vilnius, Lithuania. Just two days before that summit, Biden publicly axed the idea of inviting Ukraine to join NATO there, calling the move “premature” and insisting that Kyiv was not “ready” to join, angering Ukrainian and Eastern European officials.

In response, Ukrainian President Volodymyr Zelensky slammed the alliance’s indecision on a timeline for his country’s NATO membership as “unprecedented and absurd.”

This year, some NATO allies are advancing plans for interim security guarantees for Ukraine that would come short of alliance membership. The United Kingdom signed a deal earlier this month with Ukraine cementing military and security assistance for Ukraine that would remain in effect until it joins NATO. These agreements are modeled after U.S. relations with Israel, in which Israel gets streamlined priority in arms deals and advanced military technology. Other NATO allies, including Poland and France, are expected to follow suit.

“If Putin wins in Ukraine, he will not stop there,” British Prime Minister Rishi Sunak said in a press conference with Zelensky in London this month.

But those interim security guarantees are viewed in Kyiv as a consolation prize to the real goal of NATO membership.

Even if Ukraine received a formal invitation to join NATO, there’s an open debate on when or how it could actually join if part of its territory was still occupied by Russia. There’s a loose precedent for this in NATO history; West Germany entered the alliance while it was still divided during the Cold War, with East Germany serving as the Soviet Union’s buffer against NATO on the other side of the Iron Curtain. Yet this analogy falls flat for one obvious reason: Unlike Ukraine and Russia today, West and East Germany weren’t in the midst of a full-scale war.

Then there’s the question of how long it would take Ukraine to join even if it got the coveted formal invitation. NATO members have to unanimously approve admitting any new member, a hurdle that can cause major political disputes and diplomatic headaches within the alliance. Finland and Sweden both moved to join the alliance shortly after the start of Russia’s full-scale invasion of Ukraine in 2022. Finland has since been admitted, but Sweden is still stuck in limbo after years of tortuous negotiations with Turkey. Turkey finally greenlighted Sweden’s bid earlier this month, while Hungary, led by Putin-friendly Prime Minister Viktor Orban, is the final holdout.

Getting all 31, and likely soon 32, member states to agree to admitting Ukraine is likely to be exponentially more difficult and could take years. This week, Slovakia’s populist and pro-Russia prime minister, Robert Fico, said he would veto Ukraine’s NATO membership because admitting Ukraine to NATO would mean “nothing other than a basis for World War III.”

Some experts believe that if the United States takes a strong stand on advancing Ukraine’s NATO membership, at least most of the rest of the alliance currently waffling on the issue will follow suit.

“You do have 50 shades of gray among the allies now,” said Camille Grand, a former senior NATO official now at the European Council on Foreign Relations. Yet, he added, there’s “a large group that will sort of follow whatever the U.S. direction of travel is.”

Robbie Gramer is a diplomacy and national security reporter at Foreign Policy. Twitter: @RobbieGramer

Jack Detsch is a Pentagon and national security reporter at Foreign Policy. Twitter: @JackDetsch