President Biden told reporters Friday that he is moving U.S. troops to Eastern Europe and NATO countries in the "near term."

The president made the comment after stepping off of Air Force One following a speech in Pittsburgh. He did not say how many troops would be going, and he added that he does not have an update on the tensions between Russia and Ukraine.

Members of Ukraine's Territorial Defense Forces, volunteer military units of the Armed Forces, train in a city park in Kyiv, Ukraine, Saturday, Jan. 22, 2022. (AP Photo/Efrem Lukatsky)

UKRAINE, RUSSIA STANDOFF: ARIZONA AIR FORCE BASE COULD DEPLOY US TROOPS IF MOSCOW LAUNCHES ATTACK

Biden's remark comes as top Pentagon officials Friday said the build-up of Russian troops along Ukraine's border is the largest since the Cold War. Joint Chiefs of Staff Chairman Mark Milley warned that conflict in Eastern Europe would be "horrific." Defense Secretary Lloyd Austin stressed that it is "not inevitable," maintaining that there is "still time and space for diplomacy" as the Kremlin continues to threaten a major incursion in Ukraine. 

Biden said earlier this week there would not "be any American forces moving into Ukraine," though he hinted then that U.S. troops could be moved to Europe. The troops may head to NATO front-line countries if Russian begins a large military operation against Ukraine.

Vladimir President Vladimir Putin in Moscow, Russia, Tuesday, Jan. 25, 2022.  (Sputnik, Kremlin Pool Photo via AP)

UKRAINE CRISIS PUTS ARMY'S 82ND AIRBORNE ON HEIGHTENED ALERT, AMONG OTHER UNITS NOW IDENTIFIED

The U.S. Army's 82nd Airborne Division is one of several military units on heightened alert as Russian forces continue a military buildup on the Ukrainian border.

"I can say today that these units include elements of the 82nd Airborne Division based at Fort Bragg, which regularly, I think you all know, maintains high readiness, as well as elements of the 18th Airborne Corps, also based at Fort Bragg," Pentagon spokesman John Kirby said during a press briefing Thursday.

A serviceman takes his position in a trench at the line of separation near Yasne village, about 33,6 km (21,2 miles) south-west of Donetsk, controlled by Russia-backed separatists, eastern Ukraine, Friday, Jan. 14, 2022. (AP Photo/Alexei Alexandrov)

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The U.S. has been bracing for weeks for the possibility that Russia may launch an invasion of Ukraine, warning of dire consequences if Moscow goes through with an invasion. Over 100,000 Russian troops are at the border with Ukraine, with Kirby saying the Pentagon has continued to see a buildup of "credible combat forces" in the last 24 hours.

The White House did not immediately respond to a request for comment from Fox News.

Fox News' Michael Lee contributed to this report.