The North Atlantic Treaty Organization (NATO) has for the first time activated a military response force designed to boost the defenses of frontline nations in eastern Europe that feel vulnerable after Russia’s military assault on Ukraine.
Gen. Tod Wolters, NATO’s Supreme Allied Commander and the top U.S. military officer in Europe, said the multinational force consisting of land, air, sea and special operations troops intended to deter Russia from further aggression.
“This is an historic moment,” Wolters said in a statement. “These deterrence measures are prudent and enhance our speed, responsiveness and capability to shield and protect the one billion citizens we swore to protect.”
Read More: Here’s What We Know So Far About Russia’s Assault on Ukraine
The first-time activation of thousands of NATO troops in Europe represents the latest escalation in a volatile ground war that has no modern precedent. In recent months, U.S. and European allies have increased air-policing missions over allied nations and moved troops, naval ships and heavy weaponry eastward on the continent, near where the Russian military is operating.
Ukraine is not a NATO member, but it borders four nations that are: Poland, Slovakia, Hungary and Romania. The U.S. and other NATO allies have pledged to protect their eastern and central European members under the alliance’s defining Article 5 mutual defense commitments.
President Joe Biden has repeatedly insisted U.S. troops will not fight in Ukraine, but he has redoubled defenses in surrounding countries by moving roughly 14,000 troops eastward in Europe during the past three weeks. Washington has also provided about $650 million in military aid to the pro-Western government.
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NATO Secretary General Jens Stoltenberg said Friday he received commitments to provide additional equipment, including air defense systems, to Ukraine after leaders from the 30-member alliance held a virtual meeting. “We see rhetoric, the messages, which is strongly indicating that [Russia’s] aim is to remove the democratically-elected government in Kyiv,” he told reporters.
The Russian military advance on Kyiv is going slower than U.S. intelligence anticipated, a senior U.S. defense official said Friday, with Ukrainian forces showing stiff resistance.
“The Russians have lost a little bit of their momentum,” the official said. “They are not advancing as far or as fast as we believe they expected they would. A good indicator of that is no population centers have been taken. We also assess that Russia has yet to achieve air superiority over Ukraine.”
Despite fears that the Ukrainian military would crumble under the combat power Russia continues to pour into the country, Ukrainian command and control remains intact. Air missile defense systems are still working even though installations were destroyed by Russia’s opening salvos, and Ukrainian fighter jets continue to engage Russian warplanes, the U.S. official said.
Read More: ‘We Will Defend Ourselves.’ Photographs of Ukraine Under Attack
Russia has yet to commit most of its forces to the assault, the official cautioned, with only about a third of the more than 150,000 troops amassed on Ukraine’s borders moving in so far. Russia launched an amphibious assault Friday on the port city of Mariupol, located on the Sea of Azov. “Indications are right now that they are putting potentially thousands of naval infantry ashore there,” the official said.
Explosions continue to rock several Ukrainian cities, including the capital Kyiv, in what the Pentagon believes is the first phase of a Russian “decapitation” strategy aimed at toppling the President Volodymir Zelensky’s government. More than 200 missiles have pummeled weapons depots, military installations and other targets, the Pentagon said.
Amnesty International said Friday that Russia’s invasion has been marked by indiscriminate attacks on civilian areas and strikes on protected targets such as hospitals. Amnesty issued a report that documented three incidents estimated to have killed at least six civilians and injured at least 12. “The Russian military has shown a blatant disregard for civilian lives by using ballistic missiles and other explosive weapons with wide area effects in densely populated areas,” said Agnès Callamard, the nonprofit’s secretary general.
Read More: How Russia’s Invasion of Ukraine Could Change the Global Order Forever
At least 137 Ukrainians were killed and more than 300 injured on the first day of the invasion, Zelensky said Thursday evening. Thirteen border guards were killed Thursday on Snake Island, a 42-acre scrap of land in the Black Sea, near Romania, according to an audio recording reported by the Ukrainian news outlet Ukrayinska Pravda. Russia’s navy is heard imploring the unit to give up over radio communications. “Lay down your arms and surrender to avoid bloodshed and unnecessary deaths,” a Russian officer said. “Otherwise, you will be bombed.”
The reply from the Ukraine’s border guards was simple: “Russian warship, go f–k yourself.” Moments later, they were all killed.
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Write to W.J. Hennigan at william.hennigan@time.com