Lithuania's military says the Baltic states will seek a permanent presence of NATO troops on their territory to counter increased Russian air and naval activity.
Lithuania, Latvia, and Estonia fear they could become a target of Russian pressure after a pro-Moscow rebellion in eastern Ukraine.
All three Baltic states have sizeable Russian minorities and were part of the former Soviet Union. They have been members of NATO since 1999 and joined the European Union in 2004.
Lithuanian Army spokesman Mindaugas Neimontas said on May 14, "In reaction to the security situation in the region, as a measure of deterrence, chiefs of defense of the Baltic states will apply officially to Supreme NATO Allied Commander Europe (SACEUR) about permanent stationing of a brigade-sized NATO unit in the Baltic states."
A NATO brigade typically numbers between 3,000 and 5,000 troops and is made up of several battalions.
NATO is establishing six regional command-and-control centers in the Baltic states, Poland, Romania, and Bulgaria.
But the alliance has pledged under a 1997 agreement with Russia not to permanently station "substantial combat forces" in its eastern member countries.