Finland's Prime Minister Sanna Marin and Swedish Prime Minister Magdalena Andersson are meeting in Stockholm on Wednesday to discuss regional security matters in the aftermath of Russia's invasion of Ukraine.
On Wednesday, Finland will begin a debate that could see it putting forth an application to join the Nato military alliance that it already cooperates with. Moscow has already expressed its disapproval.
In fellow non-Nato member state Sweden, Russia's war against its neighbor Ukraine has also provoked anxiety, as well as a political face on the country's question of military non-alignment.
Russia has repeatedly said Nato expansion is a thorn in its side, while Nato maintains the alliance is defensive in nature.
What is the debate in Finland?
On Wednesday, a government-commissioned report examining the "fundamentally changed" security environment in Europe following Russia's war on Ukraine, is scheduled to be released. According to the Ministry of Foreign Affairs, the report will then make its way through parliament with an opening debate planned for next Wednesday.
Finland shares a 1,340-kilometer border with Russia. In 1917, Finland declared independence from Russia as the country descended into chaos amid the Russian revolution.
Finland also fought the Winter War in 1939 following an invasion by what was then the Soviet Union. It lost roughly 10% of its territory but managed to inflict heavy losses on the Red Army and maintain control of its capital and state.
During the Cold War, Finland was formally neutral to prevent Russia from invading. Finland referred to its position as "active neutrality," although more critical voices said that Moscow's views and values did creep into the country's political process, with the more pejorative term "Finlandization" coined in West Germany in the 1960s.
Alexander Stubb, a former prime minister of Finland who has long advocated for the country's membership in Nato, now believes it is "a foregone conclusion." However, as recently as January the current prime minister Sanna Marin called the possibility "very unlikely."
Russia's decision to invade Ukraine has led to a spike in public support from 20-30% in favor of Finland formally joining the alliance to over 50% of the population now.
What does the debate look like in Sweden?
Sweden does not share a border with Russia, but the strategic island of Gotland in the Baltic Sea could make Sweden vulnerable should a conflict erupt in the region.
Robert Dalsjo, the research director at the Swedish Defense Research Agency, said Swedes have realized "that they might find themselves in the same position as Ukraine: a lot of sympathy but no military help."
Sweden's ruling Social Democrats changed their mind on their long-held opposition to joining Nato this week.
What happens next in Helsinki and Stockholm?
Finland already cooperates heavily with the US and Nato forces, though is not protected by the mutual defense part of the treaty known as Article Five.
The Helsingen Sanomat daily polled the country's lawmakers and found half of the 200 members of parliament approve, with only 12 firmly opposed. Others have said they will announce later where they stand after detailed discussions.
Finland's parliament will hear from a range of security experts in the weeks ahead as the country moves towards a decision "before mid-summer," Marin has said. Analysts and security experts believe an application is likely sometime in June.
All 30 members of Nato would need to ratify the country's membership which could take anywhere from a few months to a year. Nato Secretary General Jens Stoltenberg has said the door for membership remains open.
While many analysts expect a joint application from the two countries, the leaders of both countries stress Finland and Sweden could ultimately reach separate conclusions on whether to join the military alliance.
Kremlin spokesman Dmitry Peskov has said if Finland joins Nato, Russia would seek to "rebalance the situation."