Finland must apply to join the NATO military alliance "without delay", Finnish President Sauli Niinisto and Prime Minister Sanna Marin said on Thursday, a major policy shift triggered by Russia's invasion of Ukraine.

Finland, which shares a 1,300 km (810 mile) border and a difficult past with Russia, has gradually stepped up its cooperation with the North Atlantic Treaty Organization as a partner since Russia annexed Crimea in 2014.

But until Russia's invasion of Ukraine, the Nordic country had refrained from joining in order to maintain friendly relations with its eastern neighbour.

"Finland must apply for NATO membership without delay," Niinisto and Marin said in a joint statement.

"We hope that the national steps still needed to make this decision will be taken rapidly within the next few days."

The view among Finns on NATO has changed rapidly after Russia initiated what it calls a "special operation" in Ukraine.

Finnish public support for joining NATO has risen to record numbers over recent months, with the latest poll by public broadcaster YLE showing 76% of Finns in favour and only 12% against, while support for membership used to linger at only around 25% for years prior to the war in Ukraine.

While military non-alignment has long satisfied many Finns as a way of staying out of conflicts, Russia's invasion of sovereign Ukraine has led an increasing number of Finns to view friendly relations with Russia as an empty phrase.

Ukraine's fate has been particularly disturbing for Finland to watch as it fought two wars with Russia between 1939 and 1944, repelling an attempted invasion but losing around 10% of its territory in the subsequent peace agreement.

Finland's rapid shift towards NATO is likely to pull along neighbouring Sweden.

 

(Reporting by Anne Kauranen and Essi Lehto, writing by Anne Kauranen and Gwladys Fouche, editing by Justyna Pawlak and Angus MacSwan)