About 8,500 U.S. troops were put on heightened alert Monday for possible deployment to Europe, ratcheting up tensions as Russia refused to back down from the threat of invading Ukraine.
The alert order was issued by Defense Secretary Lloyd Austin to units now in the U.S. that would be part of a NATO force if the alliance decides to activate a military response, Pentagon spokesman John Kirby said during a press briefing. The move includes Army brigade combat teams as well as logistics, medical, aviation and transportation units.
"We wanted to make sure that we were ready in case that call should come, and that means making sure that units that would contribute to it are as ready as they can be on as short a notice as possible," Kirby said. "Again, no final decision has been made to deploy them."
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Some of those U.S. forces could also be deployed unilaterally, and the Pentagon said more forces already stationed in Europe could be moved to NATO member countries in the continent's eastern flank.
The preparations come as diplomacy between the West and Moscow has failed to yield a breakthrough, and Russia has continued to add battalion tactical groups along the border of Ukraine and increasing forces in nearby Belarus, according to the Pentagon. The Biden administration has estimated about 100,000 Russian troops are amassed for a potential invasion.
President Joe Biden was set to meet with European leaders via video conference on Monday to discuss the growing security crisis surrounding Ukraine.
Secretary of State Antony Blinken met on Friday with Russia Foreign Minister Sergey Lavrov in an attempt to break the stalemate, and he said talks would continue. Russia has demanded assurances that Ukraine will never join NATO and that the alliance would pull back forces from its eastern edge.
The State Department issued an order Sunday for family members of U.S. embassy staff in Ukraine to leave the country.
The NATO Response Force, or NRF, is a "technologically advanced" multi-national force of about 40,000 land, air, maritime and special operations troops. The U.S. units put on alert would contribute to any NRF effort authorized by the alliance, but the Pentagon said no mission has yet been planned.
"This is about sending a strong message, that we're committed to NATO and we're committed to assuring that our allies have the capabilities they need in case they need to defend themselves," Kirby said.
Russia has shown no intentions to pull back from its buildup around Ukraine, and Kirby said it would be "irresponsible" for the Pentagon not to make preparations for a possible deployment.
-- Travis Tritten can be reached at travis.tritten@military.com. Follow him on Twitter @Travis_Tritten.
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