WASHINGTON: Sweden was set to join NATO on Thursday, capping two centuries of non-alignment and two years of torturous diplomacy overshadowed by the war in Ukraine.

Swedish Prime Minister Ulf Kristersson was visiting Washington where Secretary of State Antony Blinken was to ceremonially receive the ratification documents after the hard-fought battle to secure the green lights needed from all NATO members.

Russia’s February 2022 invasion prompted Sweden and neighbouring Finland to apply to join the bloc, ending a long-standing stance of non-alignment in both countries.

In a post to X on Thursday just hours before the ceremony, Kristersson said NATO Secretary General Jens Stoltenberg had informed him “that all NATO member states have accepted our accession protocol, and has invited Sweden to accede to the North Atlantic Treaty.” “Sweden will soon be NATO’s 32nd member,” Kristersson said.

Meanwhile, the Swedish government announced it was holding “an extraordinary government meeting this afternoon to approve Sweden’s accession to the North Atlantic Treaty.”

Afterwards, “Kristersson will deposit Sweden’s instrument of Accession with the Government of the United States. Sweden will then be a member of NATO and fully participating Ally,” the government said in a statement.

The Swedish prime minister is later in the day to attend the annual State of the Union address by President Joe Biden, who has been struggling to persuade the rival Republican Party to approve new aid to Ukraine.

Sweden’s blue and golden-yellow flag is expected to be hoisted on Monday at the Brussels headquarters of the North Atlantic Treaty Alliance.

Russia has vowed “countermeasures” over Sweden’s entry into NATO, especially if the alliance’s troops and assets deploy in the country.

Sweden and Finland, while both militarily intertwined with the United States and members of the European Union, have historically steered clear of officially joining NATO, formed in the Cold War to unite against the Soviet Union.

Sweden has not been involved in a war, including World War II, since the Napoleonic conflicts of the early 19th century.

But Finland and Sweden launched a joint bid after Russia in 2022 invaded Ukraine, which had unsuccessfully sought to join NATO — which considers an attack on one member an attack on all.