Pentagon puts 8,500 troops on heightened alert to deploy if requested by NATO

The Pentagon has notified military units in the U.S. that they should be prepared to deploy to Europe if the NATO alliance requests them, as tensions with Russia over its buildup on the border of Ukraine continue to rise. 

The vast majority of the 8,500 troops who have been put on alert would deploy as a part of the NATO Response Force if activated by NATO. Some, however, could deploy unilaterally to bolster countries on the eastern flank of NATO if the security situation in Eastern Europe deteriorates. 

The Pentagon has not yet identified which units have been put on alert, but the capabilities include additional brigade combat teams, reconnaissance, logistics, aviation, and transportation. 

U.S. forces in Europe could also be put on heightened alert to move within Europe if asked. 

Pentagon spokesman John Kirby told reporters Monday that the decision was made by President Biden to put these troops on heightened alert, and was in part the result of advice given by Defense Secretary Lloyd Austin and Chairman of the Joint Chiefs of Staff General Mark Milley. 

"As of now, the decision has been made to put these units on higher alert, and higher alert only," Kirby said. "No decisions have been made to deploy any forces from the United States at this time." 

Some of these have already been in a heightened readiness to deploy posture, and Austin decided "to shorten the tether even more," according to Kirby. Some of the units were on heightened alert to deploy within ten days if asked and now have been told they should be ready in as little as five days. 

The decision to put these forces on alert comes as NATO announced Monday it will be sending additional capabilities to the countries in the eastern flank of the alliance, and as embassies in Ukraine, including the American embassy, order some departures from the country.

Kirby said Monday that Russia has not shown signs of deescalation and has in fact built up more forces along its border with Ukraine and in Belarus in recent weeks. Russia has amassed 100,000 troops along the border with Ukraine in recent weeks, and Mr. Biden said last week that it was his "guess" that Russia plans to invade.

U.S. Secretary of State Antony Blinken told "Face the Nation" on Sunday that there would be "massive consequences" for Russia if its military forces invade Ukraine.