U.S. Says 'Thousands' of Russian Troops in East Ukraine

The United States' senior envoy to Europe alleged Wednesday that Russia had deployed "thousands and thousands" of troops to neighboring Ukraine.

Speaking to a congressional foreign affairs committee, Assistant Secretary of State Victoria Nuland also told U.S. lawmakers that Russia was flooding eastern Ukraine with military hardware.

"Since December, Russia has transferred hundreds of pieces of military equipment, including tanks, armored vehicles, rocket systems, heavy artillery," Nuland said. 

"The Russian military has its own robust command structure in eastern Ukraine ... they are funding this war, they are fueling it and commanding and controlling it."

Nuland did not specify how many Russian troops were in eastern Ukraine.

"I am not in a position to give you a definitive number in this unclassified setting," she said. 

"I would say it's in the thousands and thousands."

On Tuesday, Western leaders including U.S. President Barack Obama called for a "strong reaction" from the international community to any major violation of a ceasefire in eastern Ukraine as they sought to further pressure Russia over the conflict.

The leaders did not specify what a "major" break from the accord might be, nor what response it would provoke, but hinted at the possibility of further sanctions on Moscow.