Finland could apply to join NATO within weeks, Prime Minister Sanna Marin said Wednesday after a government report concluded that joining the Alliance would boost security in the region.

The country, which successfully fought off a Soviet invasion during World War II and has since been neutral, has long refused to join the North Atlantic Treaty Organization amid a lack of popular support for the move.

Since Russia invaded Ukraine, however, polls have shown that support for membership had surged to over 60% from below 20%. Most political parties in Helsinki now also agree Finland should become a member to boost its security.

“We have to be prepared for all kinds of actions from Russia…There is no other way to have security guarantees than under NATO’s deterrence and common defense as guaranteed by NATO’s Article 5,” Ms. Marin told reporters in Stockholm, referring to the alliance’s article that says an attack on one member is to be considered an attack on all.

Ms. Marin, who stood alongside her Swedish counterpart, Magdalena Andersson, said the decision would be made within weeks. “Everything changed when Russia invaded Ukraine… I think people’s mindsets in Finland, also in Sweden, changed and shifted very dramatically because of Russia’s actions,” Ms. Marin said.

Finland shares a border of more than 800 miles with Russia, which would become NATO’s most exposed eastern flank if the country becomes a member.

Sweden, which has been neutral for over 200 years, is considering the same move.