The US State Department said it was told Russia has accumulated tanks and artillery at deployment sites that may be given to separatist fighters in Ukraine.
The US also has its own information that Russia redeployed military forces to its border with Ukraine, State Department spokeswoman Jen Psaki said.
"We have information that additional tanks have been prepared for departure," she added.
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The win sends the Scot through to the last eight where he will face either Japan's Kei Nishikori or France's Richard Gasquet.
People "would not want" international footballer Jerome Boateng as their neighbour, according to a German politician.
The paralympian posted a time of two minutes and 57 seconds on Sunday.