NATO says it has intercepted Russian planes flying near Baltic borders up to 50 times in recent weeks.
A Russian reconnaissance aircraft flying near Latvian waters was intercepted this week by NATO fighters.
Latvian Defense Minister Raimonds Vejonis said that the increasing frequency of Russian military aircraft flying near Baltic borders shows that NATO must have a permanent presence in the region.
''The events in the recent weeks prove the alliance's solidarity amongst allies, and demonstrates that our allies will protect our security,'' he said.
Baltic leaders have repeatedly called for permanent NATO presence in the Baltic states amid the Ukraine crisis.
Flights above neutral waters are not a violation, however, Russian planes did not observe several international standards, NATO said.
NATO fighter jets had to take off to establish a visual contact and confirm they were not, for example, terrorist-kidnapped planes.
Currently, there are 12 NATO fighter jets patrolling Baltic skies including four from Poland, four from Great Britain and four from Denmark.