Lithuanian president says Russian military planes violated the Baltic country's airspace

“This is a blatant breach of international law and territorial integrity of Lithuania,” Nausėda wrote on X. “Once again, it confirms the importance of strengthening European air defence readiness.”

There was no immediate comment from Moscow.

Baltic nations already have been on heightened alert over neighboring Russia’s aggression on Ukraine. And in recent weeks, a series of mysterious drone incidents and airspace violations by Russian war planes have fueled concerns that Russian President Vladimir Putin might be testing NATO’s defensive reflexes.

Some leaders have accused Putin of waging a hybrid war in Europe. Moscow denies probing NATO’s defenses.

The Lithuanian armed forces said in a statement that about 6 p.m. local time on Thursday, two Russian military aircraft flew into Lithuanian airspace for about 700 meters (765 yards), The SU-30 aircraft and IL-78 refueling aircraft flew away after roughly 18 seconds.

The Lithuanian armed forces believe the military planes might have been conducting refueling exercises in the neighboring Russian exclave of Kaliningrad.

Two Spanish fighter jets, which had been doing NATO air policing missions, were scrambled and flew out to the area.

Earlier on Thursday, Nausėda attended a summit at the European Council building in Brussels where EU leaders endorsed a plan to ensure that Europe can defend itself against an outside attack by the end of the decade. The plan is dubbed Readiness 2030.