Finland has become NATO's 31st member, with the flag-raising ceremony taking place less than a year after the country applied to join. Historically militarily non-aligned and even cooperating with Russia on a political and economic level, Finland's stance changed after Russia invaded Ukraine and Finland in February last year.
NATO's Secretary-General called Finland's membership a historic moment, which will make the alliance stronger and Finland safer. However, the move has not been welcomed by Russia, with its defence minister saying that it will make conflict more likely and the Kremlin claiming it will have to bolster its defences in the north.
Meanwhile, Sweden, which applied to join NATO at the same time as Finland, has yet to be approved by all NATO members, with Turkey's President claiming Sweden hasn't done enough to fight terrorism. The NATO Secretary-General has said they will ensure Sweden joins.