File images of the Finnish army and images including aerial shots of the Finnish side of the Finland-Russia border, as Finland prepares for a potentially historic decision "before midsummer" on whether to apply to join NATO as a deterrent against Russian aggression. The Nordic nation of 5.5 million has traditionally been militarily non-aligned, in part to avoid provoking its eastern neighbour, with which it shares a 1,300 kilometre (830 mile) border. But Russia's invasion of Ukraine on February 24 saw public support for joining NATO double from 30 to 60 percent, according to a series of polls. FILE IMAGES of the Finnish army and the Finland-Russia border