Updated February 2, 2022 at 5:36 PM ET
President Biden is moving roughly 3,000 U.S. troops closer to Ukraine, where tensions are running high after Russian President Vladimir Putin positioned a large military force along the two countries' border.
"These are not permanent moves," Pentagon press secretary John Kirby said Wednesday, emphasizing that the forces will not fight in Ukraine.
The troops are being sent to bolster positions in Poland, Romania and Germany — a result of conversations with NATO allies and especially Romanian leaders, Kirby told NPR's All Things Considered. Kirby emphasized the obligation to defend other members of NATO, but said the movements aren't being carried out through NATO.
"It's ironic," Kirby said. "The very thing that [Putin] says he doesn't want, he's going to end up getting: a strong NATO on NATO's eastern flank and his western flank. He has himself to thank for that."
At the White House, Biden said the move is "totally consistent with what I told Putin in the beginning: as long as he's acting aggressively, we're going to make sure we reassure our NATO allies in Eastern Europe that we're there, and Article 5 is a sacred obligation."
The president was referring to the part of the NATO pact that deals with collective defense.
The U.S. already has some 60,000 troops based in Europe. Russia has massed about 127,000 troops near its Ukrainian border, former Ukrainian defense minister Andriy Zagorodnyuk recently told NPR. In Zagorodnyuk's view, the Russian force isn't large enough to mount a full-scale invasion.
The U.S. troop shift has two main steps. In the first, about 1,000 personnel from a Stryker squadron in the 2nd Cavalry Regiment based in Vilseck, Germany, will deploy to Romania, where more than 900 U.S. service members are already stationed.
The force will have "armored fighting vehicles to deter aggression and enhance our defensive capabilities in frontline Allied states during this period of elevated risk," the Pentagon said in a summary of the plan.
The second part of the operation will send around 3,000 total troops to Poland and Germany. Those personnel will be drawn from Fort Bragg in North Carolina — about 1,700 members of the 82nd Airborne Division and 300 service members of the 18th Airborne Corps.
As part of those plan, the 18th Airborne Corps will move a "Joint Task Force-capable headquarters" to Germany, the Pentagon says.
The U.S. is keeping another 8,500 personnel in reserve. Those troops have been on a heightened alert since Jan. 24 and are available if a NATO Response Force is activated.
Kirby told NPR that deploying additional personnel or relocating troops isn't out of the question.
"And we certainly have not ruled out the possibility that the president and the secretary of defense might find it suitable and necessary to send additional troops from the United States to Europe," Kirby said. "We're going to watch this day by day."
NPR's Tom Bowman and Franco Ordoñez contributed to this report.
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