By ZEKE MILLER
WASHINGTON (AP) — President Joe Biden formally welcomed Finland and Sweden joining the NATO alliance Tuesday as he signed the instruments of ratification that delivered the U.S.’s formal backing of the Nordic nations entering the mutual defense pact. It’s part of a reshaping of the European security posture after Russia’s invasion of Ukraine. The Senate last week approved the two, once-non-aligned nations joining the alliance in a rare 95-1 vote. The countries sought out NATO membership earlier this year to guarantee their security in the wake of Russian President Vladimir Putin’s offensive in Ukraine. All 30 exiting members of the North Atlantic Treaty Organization must consent before Finland and Sweden can officially accede into the alliance.