The Swedish military will participate in monitoring and protecting Finnish territory with Gripen fighter jets and corvettes, at least until the end of 2026, the Finnish Armed Forces announced today.

“Swedish equipment will particularly strengthen air surveillance, freeing up the Finnish Defense Forces’ own resources to deter violations and incidents, if necessary,” the Finnish military said in a statement.

The neighboring countries, the two newest members of NATO, already have close bilateral defense cooperation. Finland shares a 1,340-kilometer-long eastern border with Russia.

“Sweden responded to a Finnish request to strengthen its air defense due to the deteriorating security situation,” Swedish Defense Minister Pål Jonson told Reuters, adding that under the agreement, the Swedish armed forces can, if necessary, help Finland repel violations of Finnish territory.

In addition to fighter jets and vessels with capabilities for combating unmanned aircraft, Sweden can also contribute ground-based counter-drone systems, he said.

Military drones entering the airspace of Finland, Estonia, Latvia, and Lithuania are fueling concerns that the war in Ukraine is spreading to NATO’s northern borders with Russia.

Ukraine is stepping up attacks on Russian ports in the Baltic Sea, and some Ukrainian drones have missed their targets, raising security concerns in neighboring countries.

Swedish company SAAB, the manufacturer of the Gripen, said separately today that it had won a Finnish procurement tender worth 1.2 billion kronor ($126 million) and would deliver the RBS 70 NG portable air-defense missile system to the country.