NATO's Baltic Operations 24 kicks off this week, featuring Sweden participating as a NATO member for the first time.
The exercise includes 20 NATO allies, including Estonia, Latvia, Lithuania and Poland.
More than 50 ships, 85 aircraft, and 9,000 personnel will participate.
NATO claims the presence of Sweden as a member bolsters the alliance, sending a clear message to Russia, which is now the only nonmember bordering the Baltic Sea.