Finland on Tuesday became the 31st member to join the NATO alliance. This will be a massive blow for Russia with historic realignment triggered by Ukraine war.
The Kremlin has already responded to Finland's accession by saying that they would be forced to take "counter-measures".
Finland's membership represents a major change in Europe's security landscape. The country adopted neutrality after its defeat by the Soviets in World War II.
But its leaders signalled they wanted to join the alliance just months after Russian President Vladimir Putin's invasion of Ukraine sent a shiver of fear through Moscow's neighbours.
The move is a strategic and political blow to Putin, who has long complained about NATO's expansion toward Russia and partly used that as a justification for the invasion.
