The US Senate on Tuesday took its earliest decisions for supporting the membership of Sweden and Finland in NATO.
The 30 members of NATO's parliaments should approve the membership of the two Nordic states.
The Senate Foreign Relations Committee approved the resolution as a representation of the US' full support to the NATO members amid the military operations of Russia in Ukraine.
Democratic Senator Bob Menendez, the chairman of the committee, described the resolution as "undoubtedly one of the most consequential foreign policy successes in recent years."
"As US foreign policy priorities evolve to account for a changing world, what is self-evident is the future of the transatlantic partnership will be even more intertwined and integrated thanks to (Russian President Vladimir) Putin's recklessness," he added.
Early this month, NATO members are set to sign the protocols of accession needed to invite Sweden and Finland to join the alliance at a ceremony at the alliance’s headquarters in Brussels.
Swedish Foreign Minister Anne Linde and her Finnish counterpart Pekka Haavisto will attend the ceremony, along with representatives of the 30 current members of the Western Military Alliance.
The protocols allow NATO Secretary-General Jens Stoltenberg to formally invite Sweden and Finland to join the alliance, but the ratification process may see both countries continue to wait.
Alliance members must pass advocacy protocols, a process that usually includes national parliaments. It is estimated that this will last another six to eight months before Sweden and Finland can join.