Finland and Sweden formally applied to join NATO on Wednesday, prompted by Russia’s invasion of Ukraine and triggering one of the most significant changes in Europe’s security architecture in decades.
The applications came after more than 250 Ukrainian fighters surrendered to Russian forces at the Azovstal steelworks in Mariupol after weeks of resistance, bringing an end to the most devastating siege of Russia’s war in Ukraine.
Finland and Sweden were both neutral throughout the Cold War and their decision to join NATO reflects the sweeping shift in public opinion in the Nordic region since Russia’s Feb. 24 invasion.
It also brings about an expansion of the Western alliance that Russian President Vladimir Putin had long invoked as one of the main justifications for ordering his “special military operation” in Ukraine in February.
“This is a historic moment, which we must seize,” NATO Secretary-General Jens Stoltenberg said at a ceremony in which the Swedish and Finnish ambassadors to the alliance handed over their application letters.
Ratification of all 30 allied parliaments could take up to a year, diplomats say.
Turkey has surprised its allies in recent days by saying it had reservations about the new prospective members, but Stoltenberg said he thought the issues could be overcome.
Ankara has said it wants the Nordic countries to halt support for Kurdish militant groups present on their territory and lift bans on some sales of arms to Turkey.
U.S. President Joe Biden will host the leaders of Sweden and Finland at the White House on Thursday to discuss the applications, the White House said.
After weeks in which Russia threatened retaliation against the NATO plans, Putin appeared to abruptly climb down, saying in a speech on Monday that Russia had “no problems” with either Finland or Sweden, and that their NATO membership would not be an issue unless the alliance sent more troops or weapons there.
The steelworks surrender in Mariupol allowed Putin to claim a rare victory in a campaign which many military analysts say has stalled.
While both sides spoke of a deal under which all Ukrainian troops would abandon the steelworks, many details were not yet public, including how many fighters still remained inside, and whether any form of prisoner swap had been agreed.