Pentagon Press Secretary Navy Rear Adm. John Kirby said this, Censor.NET reports, citing the US Department of Defense.
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Russia continues to maintain at least 10,000 troops near the Ukrainian border, Kirby said. "It's difficult to pin it down to a specific number but they continue to be reinforced."
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Kirby said the Russian troops are in combined arms battalions and constitute "very capable, very ready" forces.
"And as I've said before, they are close to the border -- within 50 kilometers of the border."
Kirby announced the Obama administration has asked Congress for authority to spend $19 million next year to train and equip Ukrainian National Guard forces to build capacity for internal defense.
American support to Ukraine will remain non-lethal, Kirby said. "We are not assisting them with issues of targeting," he said. "We continue to review requests for military assistance from the government of Ukraine through an interagency process."