Finland's legislature voted 188-8 on Tuesday to approve a bid for NATO membership, the same day as Sweden's foreign minister signed her country's application.
The two nations have accelerated moves to join the Western defence alliance following Russia's invasion of Ukraine. Finland borders Russia, while traditionally neutral Sweden has seen a groundswell of public support for joining the US-led alliance.
The Finnish vote, which came after a two-day debate, clears the way for an application for membership.
President Sauli Niinistö and Prime Minister Sanna Marin had already declared on Sunday that they wanted to submit an application.
Niinistö now has to sign the application before it can be handed in together with Sweden's document at NATO's headquarters in Brussels.
Sweden's Foreign Minister Ann Linde put pen to paper on Tuesday, a day after the government announced it wanted to become a NATO member.
"Our NATO application is now formally signed," Linde wrote on her Twitter account. "This feels big, it feels serious, it feels like we have landed on what we believe is best for Sweden after all."
Increase 'capacity to react'
The future NATO membership of Sweden and Finland would "strengthen" the European Union, top EU diplomat Josep Borrell said at a meeting of EU defence ministers in Brussels.
The accession of the two Nordic countries to the military alliance would also increase the EU’s "capacity to react" to threats along its border, Borrell added.
According to Borrell, NATO’s potential enlargement is "the contrary of what Putin was willing to achieve" by invading Ukraine as Russian President Vladimir Putin "was trying to stop the development of NATO [along] the borders of Russia."
Borrell added that he "hopes NATO will be able to overcome" Turkey’s objections to Finland and Sweden’s bid.
Turkish President Recep Tayyip Erdogan said on Monday he could not agree to the accession of countries that have imposed sanctions on his country and repeated allegations that both nations support "terrorist organizations."
The membership applications from Finland and Sweden must be approved by all 30 NATO states.
While NATO Secretary General Jens Stoltenberg has repeatedly emphasized in recent weeks that the two Nordic countries are most welcome in the alliance, it is now considered certain that Turkey will attach conditions to their admission.
Diplomats to Ankara
Finnish and Swedish diplomats plan to travel to Ankara this week to talk to representatives of the Turkish Foreign Ministry.
"Turkey's statements have quickly changed and hardened in recent days. But I am sure we can resolve the situation through constructive talks," Niinistö told the Swedish parliament on Tuesday.
Niinistö had arrived in Stockholm earlier for a two-day state visit.
Sweden's King Carl XVI Gustaf stressed his country's intention to join NATO "simultaneously and in agreement with Finland."
"This is a historic choice that we are making side by side with our brother country," he said at a joint press conference with Niinistö.
