A vote in Hungary's parliament allowed Sweden to clear the final obstacle to joining NATO, expanding the Western military alliance to 32 members.
Within days, Russian President Vladimir Putin used his annual State of the Nation address to threaten the use of nuclear weapons against NATO countries if they send forces to help defend Ukraine.
“They must understand that we also have weapons that can hit targets on their territory,” he told Russia's Federal Assembly on Thursday. “All this really threatens a conflict with the use of nuclear weapons and the destruction of civilization. Don’t they get that?”
Putin spoke ahead of a presidential election in mid-March that is certain to hand him another six-year term because the Kremlin excluded any real opponents. Three other candidates have been allowed to run, but each of them expressed support for Putin.
Sweden's successful bid, clinched by Hungary's vote on Monday, makes it the second country after Finland to join NATO in response to Russia's all-out invasion of Ukraine in Feb. 2022.
The bid required approval by all NATO countries, including Turkey and Hungary which each demanded concessions.
Hungarian Prime Minister Viktor Orban, who is Russian President Vladimir Putin's closest European Union ally, pressured Swedish Prime Minister Ulf Kristersson to sell Hungary more Swedish-built fighter jets.
Turkish President Recep Tayyip Erdoğan prodded the United States to sell his nation F-16 fighter jets, other countries to lift arms embargoes, and Sweden to crack down on anti-Islam activists and pro-Kurdish groups.
"This is a historic day. The parliaments of all NATO member states have now voted in favor of Swedish accession to NATO," Kristersson said. "Sweden stands ready to shoulder its responsibility for Euro-Atlantic security."
Last year, NATO welcomed Finland as the 31st member in the wake of Russia's brutal war on Ukraine, the largest attack on a European country since World War II.
'Stronger and safer'
The war – and NATO's subsequent expansion with Finland and Sweden joining – has upended the European defense landscape.
Finland's decision marked a new course after decades of official nonalignment and more than doubled the length of the 1,215 kilometers (755 miles) of borders that NATO member nations share with Russia. Finland and Russia share a 1,340-kilometer (830-mile) border.
Even with Finland in its ranks, however, NATO covers just 13% of the 20,000 kilometers of land borders that Russia shares with 14 other countries.
Sweden does not share a border with Russia, but it has a coastline stretching 3,218 kilometers (2,000 mile) to its east along the Baltic Sea, where Russia's Baltic Fleet operates out of its base in Kaliningrad.
Sweden's bid to join NATO had been in jeopardy after a protester was allowed to burn a copy of the Koran outside the Turkish embassy at Stockholm in Jan. 2023.
Putin considers NATO's eastward expansion a threat, while NATO insists it is a defensive alliance to protect its member nations and that its exercises and military deployments are not directed against Russia or any other country.
NATO Secretary General Jens Stoltenberg, a former prime minister of Norway, welcomed the Hungarian parliament’s vote.
"Now that all Allies have approved, Sweden will become the 32nd NATO ally," he said. "Sweden’s membership will make us all stronger and safer."
This story has been updated with additional details.
