Russia Accuses U.S. of Smear Campaign
Says it rejects "unfounded public insinuations."
Russia has accused the US of launching a "smear campaign" over its alleged involvement in the conflict in Ukraine.
The foreign ministry in Moscow said on Friday it rejects "unfounded public insinuations" from the US government.
But the Pentagon says it believes the movement of Russian heavy-calibre artillery systems across the border into Ukraine is "imminent."