NATO Secretary-General Jens Stoltenberg announced Friday that the alliance has activated elements of the 40,000-troop NATO Response Force (NRF) for the first time, warning at a press conference: “The Kremlin’s objectives are not limited to Ukraine.”

Why it matters: Stoltenberg has called Russia’s invasion of Ukraine “the most serious security crisis we have faced in Europe for decades.” The NRF will deploy “on land, at sea, and in the air” in eastern Europe for the purposes of collective defense.

Details: The secretary general said that the size of the NRF has tripled since 2014, but that not all forces would be deployed. He also said that NATO countries would be providing additional weapons and air-defense systems to Ukraine at the request of its government.