Service members of the Ukrainian Armed Forces drive a military vehicle during military exercises in Kharkiv region, Ukraine February 10, 2022.
Vyacheslav Madiyevskyy | Reuters
WASHINGTON – President Joe Biden's national security advisor Jake Sullivan gave a grim description Sunday of what a Russian invasion of Ukraine might look like and urged Americans to depart the country immediately.
"If there is a military invasion of Ukraine by Russia, it's likely to begin with a significant barrage of missiles and bomb attacks," Sullivan said on CNN's "State of the Union" program.
"It would then be followed by an onslaught of a ground force moving across the Ukrainian frontier," he said, adding that there would be a substantial number of civilians caught in the crossfire.
Sullivan said that in the past 10 days the Kremlin has accelerated its extraordinary military buildup along Ukraine's border. Russia's current force posture in the region could "launch a military action very, very rapidly," he said.
For months, the U.S. and its Western allies have watched a steady buildup of Kremlin forces along Ukraine's border with Russia and Belarus. The increased military presence mimics Russia's playbook ahead of its 2014 illegal annexation of Crimea, a peninsula on the Black Sea, which sparked international uproar and triggered sanctions against Moscow.
Biden, who is spending the weekend at Camp David, is slated to speak with Ukrainian President Volodymyr Zelenskyy on Sunday. The call follows Biden's Saturday call with Russian President Vladimir Putin.
The White House said Biden's conversation with Putin began at 11:04 a.m. ET and lasted for about an hour.
The president warned his Russian counterpart that if there is a further invasion of Ukraine, Washington and its allies will impose "swift and severe costs." Biden said that while the U.S. remains prepared to engage in diplomacy, "we are equally prepared for other scenarios."
Last month, the Pentagon's top officials warned that the aftermath of a Russian invasion of Ukraine would be "horrific."
"Given the type of forces that are arrayed, the ground maneuver forces, the artillery, the ballistic missiles, the air forces, all of it packaged together. If that was unleashed on Ukraine, it would be significant, very significant, and it would result in a significant amount of casualties," Chairman of the Joint Chiefs of Staff U.S. Army Gen. Mark Milley told reporters at the Pentagon on Jan. 28.
"It would be horrific," added Milley.
Milley, the nation's highest-ranking military officer, said that Russia's posture along Ukraine's border was unlike anything he has seen during his four-decade military career.
Over the weekend, Secretary of Defense Lloyd Austin ordered U.S. troops who deployed to Ukraine last year to leave the country and reposition elsewhere in Europe.
In November, 160 members of the Florida National Guard, assigned to the 53rd Infantry Brigade Combat Team, deployed to Ukraine to train with local forces.
"The Secretary made this decision out of an abundance of caution — with the safety and security of our personnel foremost in mind — and informed by the State Department's guidance on U.S. personnel in Ukraine," Pentagon spokesman John Kirby wrote in a statement.
"This repositioning does not signify a change in our determination to support Ukraine's Armed Forces, but will provide flexibility in assuring allies and deterring aggression," he added.
Meanwhile, the State Department said Saturday that it would reduce its diplomatic staff at the U.S. Embassy in Kyiv to the "bare minimum."