The Finnish foreign minister Pekka Haavisto handed the accession document Wednesday, to United States secretary of state, Antony Blinken who declared Finland the 31st member. The minister said "The task is to give to you for the deposit also our ratification for Swedish membership."
A military band played Finland's national anthem followed by the Nato hymn, as the Nordic nation's white-and-blue flag joined a circle of 30 other flags.. Beyond the perimeter fence a small group of protesters waving Ukrainian flags chanted "Ukraine in Nato," a reminder of why non-aligned Finland had asked to join along with Sweden in May 2022.
Finland shares a 832-mile eastern frontier with Russia and after the war in Ukraine began Helsinki chose the protection of Nato's Article Five, which says an attack on one member is an attack on all.
Russia's invasion prompted a 80% surge in Finnish public opinion in favor of joining Nato. Accession to the military alliance means if Finland were invaded or attacked, the other 30 members would come to its aid.
"It is a great day for Finland," said Finnish President Sauli Niinisto, proclaiming a new era for his country. Finland would be a reliable ally and its membership would not be a threat to anyone, he said. "Security and stability are those elements which we feel very strongly; if people can live in secure stable circumstances that's the basic element of happy life."
"This will make Finland safer and Nato stronger," said Secretary General Jens Stoltenberg earlier, describing it as a proud day for him and the alliance. "President Putin had a declared goal of the invasion of Ukraine to get less Nato along its borders and no more membership in Europe, he's getting exactly the opposite."
Blinken said he was "tempted to say this is maybe the one thing we can thank Mr Putin for, because he once again here has precipitated something he claims to want to prevent by Russia's aggression."
Kremlin's spokesman Dmitry Peskov reportedly said Russia would be watching closely how Nato used Finnish territory "in terms of basing weapons systems and infrastructure there which will be right up close to our borders, potentially threatening us."
"Based on that, measures will be taken," he said.
Sweden's own application to the military alliance has for now become stuck, as Hungary and Turkey are yet to approve of it.