Sweden has officially become the 32nd member of Nato after it completed its accession process in Washington.
The handover of documents took place at a ceremony two years after Sweden applied to join the military alliance following Russia’s full-scale invasion of Ukraine.
Swedish Prime Minister Ulf Kristersson said that “unity and solidarity” would be Sweden’s “guiding lights”.
“Good things come to those who wait,” US Secretary of State Blinken said.
“Our defensive alliance is now stronger and larger than it’s ever been,” he added, thanking Sweden for its “resilience”.
“This has been a little bit of a road but we’ve known from day one that we would be here one day,” Mr Blinken said.
Nato Secretary-General Jens Stoltenberg said in a statement on X that Sweden brings with it “capable armed forces and a first-class defence industry” and that the alliance had become “stronger and safer”.
Sweden applied to join the defence alliance after Russia’s full-scale invasion of Ukraine in 2022 – but its request was blocked by two members.
Turkey initially withheld approval in a row over what it called Sweden’s support to Kurdish separatists. It eventually lifted its veto in January of this year.
Hungary’s Prime Minister Viktor Orban accused Sweden of being hostile to it and delayed its approval until last week, when the Hungarian parliament eventually voted to ratify the bid.
All Nato members are expected to help an ally which comes under attack.
Mr Blinken recalled Sweden’s 200-year policy of non-alignment which lasted until Russia invaded Ukraine, saying that Nato expansion was not “foreordained” or “foreseeable”.
Mr Kristersson said: “We are humble, but we are also proud. We will live up to all expectations.”
“We share burdens, responsibilities and risk with other allies.”
He added that security situation in the region had not been this serious since World War Two, and added that Sweden was joining Nato both to provide and to gain security.
Finland formally joined in April last year, doubling the length of the alliance’s border with Russia.
On Monday a flag-raising ceremony to mark Sweden’s accession will take place at the Nato headquarters in Brussels.
