NATO on Tuesday, June 14 reinforced its defenses against Russia from the Baltic to the Black Sea, delivering what NATO’s chief called a clear message to Moscow that “if any of our allies is attacked the whole alliance will respond as one,” the Associated Press reports.


Jens Stoltenberg, the alliance secretary-general, told a news conference that NATO defense ministers agreed to deploy four multinational battalions on a rotational basis to Estonia, Latvia, Lithuania and Poland.


He said the ministers also agreed on “tailored measures” to enhance “defense and deterrence” in the Black Sea region, including the advance stockpiling of equipment and supplies.


“NATO is an alliance that delivers,” Stoltenberg said., according to AP.


Earlier, as the defense ministers began the first of two days of meetings at NATO headquarters, the secretary-general called “defending our territory and protecting our people” NATO’s primary task.


The ministers’ meetings are meant to set the stage for NATO’s summit next month from July 8-9 in Warsaw. On Tuesday and Wednesday, ministers are also expected to agree to cooperate more closely with the European Union in security affairs, discuss how to improve NATO cyberdefense, intelligence-sharing and decision-making to face current challenges, and meet with Ukraine’s defense minister.


Without disclosing details, Stoltenberg also said “we will establish a framework to deal with threats and challenges from the south” — NATO speak for the Islamic extremist violence that has become widespread in the Middle East and North Africa.


The U.S., Britain and Germany have already committed to spearheading the development of three of the four battalions earmarked for Poland, Estonia, Latvia and Lithuania. A senior U.S. official said Canadian leaders are currently meeting to discuss the possibility that they would coordinate the development of the fourth battalion, AP says.


Canadian defense spokeswoman Ashley Lemire said that, “Unfortunately, we are not in a position to provide any additional details at this time. As a committed NATO ally, Canada is actively considering options to effectively contribute to NATO’s strengthened defense and deterrence posture.”


U.S. officials said it’s not yet clear whether the Pentagon will use troops currently in Europe to form its battalion or bring in others. U.S. Defense Secretary Ash Carter told reporters Monday that the U.S. may well contribute most or all of the 800-1,000 troops needed for the unit.