The US Senate delivered near-unanimous bipartisan approval to Nato membership for Finland and Sweden on Wednesday, calling expansion of the western defensive bloc a “slam-dunk” for US national security and a day of reckoning for Vladimir Putin.

The 95-1 vote for the candidacy of two European countries that, until Russia’s war against Ukraine, had long avoided military alliances took a crucial step toward expansion of the North Atlantic Treaty Organization and its 73-year-old pact of mutual defense among the United States and democratic allies in Europe.

Joe Biden, who has been the principal player rallying global economic and material support for Ukraine, has sought quick entry for the two previously non-militarily aligned northern European countries.

Approval from all member countries – currently, 30 – is required. The candidacies of Finland and Sweden have won ratification from more than half of the Nato member countries in the roughly three months since the two applied.

“It sends a warning shot to tyrants around the world who believe free democracies are just up for grabs,” said Senator Amy Klobuchar, a Minnesota Democrat, before the vote.

“Russia’s unprovoked invasion has changed the way we think about world security,” she added.

The Senate minority leader, Mitch McConnell, who visited Kyiv earlier this year, urged unanimous approval. Speaking to the Senate, McConnell cited Finland’s and Sweden’s well-funded, modernizing militaries and their experience working with US forces and weapons systems, calling the decision a “slam-dunk for national security” of the United States.

“Their accession will make Nato stronger and America more secure. If any senator is looking for a defensible excuse to vote no, I wish them good luck,” McConnell said.

Senator Josh Hawley, a Missouri Republican who often aligns his positions with those of the most ardent supporters of Donald Trump, has been one of the few to speak in opposition. Hawley took the Senate floor to call European security alliances a distraction from what he called the United States’ chief rival – China, not Russia.

“We can do more in Europe … devote more resources, more firepower … or do what we need to do to deter Asia and China. We cannot do both,” Hawley said, calling his a “classic nationalist approach” to foreign policy.

US state and defense department officials consider the two countries net “security providers”, strengthening Nato’s defense posture in the Baltics in particular. Finland is expected to exceed Nato’s 2% GDP defense spending target in 2022, and Sweden has committed to meet the 2% goal.

Sweden and Finland applied in May, setting aside their longtime stance of military non-alignment. It was a major shift of security arrangements for the two countries after neighboring Russia launched its war on Ukraine in late February. Biden encouraged their joining and welcomed the two countries’ government heads to the White House in May.

The US and its European allies have rallied with newfound partnership in the face of the Russian president’s aggression, strengthening the alliance formed after the second world war.

“Enlarging Nato is exactly the opposite of what Putin envisioned when he ordered his tanks to invade Ukraine,” Senator Bob Menendez, a New Jersey Democrat and chairman of the Senate Foreign relations committee, said on Wednesday, adding that the west could not allow Russia to “launch invasions of countries”.

Biden sent the protocols to the Senate for review in July, launching a notably speedy process in the typically divided and slower-moving chamber.

Each member government in Nato must give its approval for any new member to join. The process ran into unexpected trouble when Turkey raised concerns over adding Sweden and Finland, accusing the two of being soft on banned Turkish Kurdish exile groups. Turkey’s objections still threaten the two countries’ membership.