'Finland must apply for NATO membership without delay,' say the country's president and prime minister.
President Sauli Niinisto and Prime Minister Sanna Marin made the joint announcement on Thursday morning.
"During this spring, an important discussion on Finland's possible NATO membership has taken place," they said. "Time has been needed to let parliament and the whole society establish their stands on the matter.
"Time has been needed for close international contacts with NATO and its member countries, as well as with Sweden. We have wanted to give the discussion the space it required.
"Now that the moment of decision-making is near, we state our equal views, also for information to the parliamentary groups and parties.
"NATO membership would strengthen Finland's security. As a member of NATO, Finland would strengthen the entire defence alliance.
"Finland must apply for NATO membership without delay. We hope that the national steps still needed to make this decision will be taken rapidly within the next few days."
Marin has said the invasion of Ukraine had "changed everything" in terms of security for Finland, which shares a 1,340-kilometre border with Russia.
Finland's foreign affairs minister, Pekka Haavisto, speaking at the European Parliament's foreign affairs committee around the time of the announcement, said Russia's invasion of Ukraine had "altered European and Finnish security".
But, he added, Finland is not facing "an immediate military threat".
"Finland's long-term partnership with Nato is close and wide-ranging" and membership would "strengthen the security and stability of the Baltic Sea" area.
Meanwhile neighbour Sweden is also expected to announce whether it will ask to join NATO, too.
The governing Social Democratic parties in both countries are set to present their positions this weekend.
Coming out in favour of joining is a historic development: Finland adopted neutrality after being defeated by the Soviet Union in World War II.
Along with Ukrainian resistance and Western sanctions, if either decided to join it would be one of the most significant ways in which the invasion appears to have backfired on Russian President Vladimir Putin, who cited NATO expansion as one of the reasons for attacking Ukraine.
The Kremlin has warned of “military and political repercussions” if the Swedes and Finns decide to join NATO.
Dmitry Medvedev, the former Russian president who is deputy head of Russia’s Security Council, said last month it would force Moscow to strengthen its military presence in the Baltic region.
However, analysts say military action against the Nordic countries appears unlikely, given how bogged down Russian forces are in Ukraine.