Russia has withdrawn "several thousand" military personnel from the Ukrainian border in the past few days but tens of thousands of soldiers remain deployed in the region, a U.S. defense official said Tuesday.
The official, speaking on condition of anonymity, said Russian troops "continue their repositioning and to move off the border."
Russian President Vladimir Putin, who ordered the deployment of close to 40,000 troops on the Russia-Ukraine border in March, according to NATO, said on May 19 the soldiers had been recalled to their garrisons.
Estimating the Russian drawdown in the "thousands," the US official added that "tens of thousands" of troops remained massed on the border.
"There are still enough forces there to create all sorts of destabilization," the official said.
Ukraine's army said Tuesday it had regained control of the airport serving Donetsk in eastern Ukraine after fierce fighting with pro-Russian militants.
Putin, who is accused of supporting the separatists, demanded that Ukrainian authorities immediately halt operations against the militants.
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