Sweden Officially Joins NATO, Ending Decades Of Post-World War II Neutrality

An empty flagpole stands between the national flags of France and Estonia outside NATO headquarters in Brussels, Monday, April 3, 2023. Finland awaits an official green light to become the 31st member of the world's biggest security alliance as NATO foreign ministers prepare to meet in Brussels on Tuesday and Wednesday. (AP Photo/Virginia Mayo)

WASHINGTON (AP) — Sweden has formally joined NATO as the 32nd member of the transatlantic military alliance, ending decades of post-World War II neutrality and centuries of broader non-alignment.

Sweden’s membership comes as concerns about Russian aggression in Europe have spiked following Russia’s 2022 invasion of Ukraine.

Swedish Prime Minister Ulf Kristersson and U.S. Secretary of State Antony Blinken presided at a Washington ceremony Thursday when the “instrument of accession” for Sweden to join NATO was deposited at the State Department.

Sweden and Finland both abandoned long-standing neutrality that had been a hallmark of the Nordic states’ Cold War foreign policy after Russia invaded Ukraine.

Finland joined NATO last year.