The Finnish foreign minister has said Russia "remains a significant threat" to its security even after joining NATO last year, and that the Northern European country will continue to focus on the development of its defense capabilities.

Noting that Sweden, Finland's neighbor, is also seeking NATO membership, Elina Valtonen said in a recent interview with Kyodo News that both countries joining the framework will "lead to more stability and security" not just in Northern Europe, but in the Baltic Sea and throughout the continent as a whole.

Finnish Foreign Minister Elina Valtonen gives an interview in Helsinki on Jan. 8, 2024. (Kyodo) ==Kyodo

Finland, which shares a 1,300-kilometer-long border with Russia, joined NATO in April last year, marking an end to its decades-long military neutrality due to fears about the threat posed by Russia following its invasion of Ukraine that began in February 2022.

Russia "is an aggressive and imperialist state that does not respect international law and the U.N. Charter," Valtonen said Monday. "With the invasion, it has shown its true face. We have to prepare for the fact that (it) will remain a significant threat towards our security and values for a very long time."

Cyberattacks from Russia have continued even after Finland became an official member of the North Atlantic Treaty Organization, Valtonen said, and she condemned Moscow for sending illegal immigrants into the country across its eastern border.

She also expressed concern about Russian espionage activities in Finland, pointing to Moscow's "increasing hostility" toward her country.

Before the invasion, "We thought that perhaps Finland didn't need membership -- we have our own defenses, we have strong cooperation. We tried to maintain some sort of relationship with Russia. But now there is no relationship, and we just have to make sure that we can defend and deter effectively," Valtonen said.

Valtonen met her Japanese counterpart Yoko Kamikawa in Helsinki on Tuesday and expressed her desire to further deepen the relationship between the two countries in areas such as defense and security.

"We value Japan's stance towards Russia's aggression in Ukraine very highly. Japan strongly stands for (our) common values in the G7 and G20," she said.