NATO announced this week its four multinational battle groups positioned in Estonia, Latvia, Lithuania, and Poland are now fully operational and it's rapid-deployment force based in Germany has been tripled in size.
The statement indicates the Canadian-led Latvian battle group was certified this week, bringing all four units to full strength. It continues:
In response to a changed security environment, Allied leaders decided at the Warsaw Summit in 2016 to enhance NATO’s military presence in the eastern part of the Alliance. Since then, four multinational battle groups totaling approximately 4,500 troops have deployed to the Baltic nations and Poland. Canada leads the battle group in Latvia, with contributions by Albania, Italy, Poland, Slovenia and Spain. Germany leads the battle group in Lithuania, with contributions by Belgium, Luxembourg, the Netherlands and Norway. The United Kingdom leads the battle group in Estonia, with contributions by France. The United States leads the battle group in Poland, with contributions by Romania and the UK.
These forces are a defensive and proportionate deterrent force, fully in line with NATO’s international commitments. They send a clear message that an attack on one Ally would be met by troops from across the Alliance.
The four battle groups are one part of the Alliance’s response to Russia’s use of force against its neighbors and its military build-up in the Baltic region and beyond. NATO is also strengthening its multinational presence in the Black Sea region, based around a Romanian-led multinational framework brigade. The Alliance has also tripled the size of the NATO Response Force to 40,000—with a high-readiness Spearhead Force at its core—and set up eight small headquarters (NATO Force Integration Units) to facilitate training and reinforcements.
The Defense Department states there are approximately 3,500 U.S. soldiers and nearly 100 tanks in Poland.