WASHINGTON — The Pentagon said Friday that Russia was moving troops and adding heavier artillery near the Ukraine border, where separatists are battling government forces, in the latest escalation of Moscow's involvement in the conflict.
Col. Steve Warren, a Pentagon spokesman, said U.S. intelligence reports show Russia was planning to give the separatists up to a dozen 200mm rocket launchers, a system more powerful than the rebels have received before.
The arms have been moved near Russia's southwest border with Ukraine, and their movement across the border appeared "imminent," Warren said.
U.S. officials said Russia was stepping up its direct role in the conflict after gains by Ukrainian government forces, who reported retaking the city of Lysychansk in eastern Ukraine from pro-Russia separatists. After the downing of a Malaysian jetliner over Ukraine last week, President Barack Obama had called for a cease-fire in the conflict and for Moscow to de-escalate its role.
Instead, "for the past several days, Russian forces using Russian artillery from Russian soil have conducted attacks against Ukrainian military positions," Warren said.
The Russians have also increased their troop presence in the border region to about 12,000, he said.
Russia on Friday called the U.S. accusations of Moscow's involvement in the Ukrainian conflict a "smear campaign."
The U.S. ambassador to Ukraine, Geoffrey Pyatt, sharply criticized Russia's behavior.
Russia could "take this crisis as an opportunity to put things back on a diplomatic track; instead, what we have seen from the Kremlin is the pouring of gasoline on the fire," Pyatt said.
Russian President Vladimir Putin "can end this with one phone call," he said.
Putin has denied supplying weapons to the separatists, who are seeking independence and possible annexation by Russia, and said he seeks a diplomatic solution to the conflict in eastern Ukraine.
Pyatt also expressed frustration over the actions of the separatists, who control the Malaysia Airlines Flight 17 wreckage site.
Dutch investigators have said they continue to be thwarted in their efforts to gain full access to the area, and inspectors from many countries remain grounded in Kiev, the Ukrainian capital, or at home worrying about the security of the site.
A small number of investigators, including some from Malaysia, where the flight was headed, and the Netherlands, where it originated, have been able to reach the zone, and wreckage has sat unguarded — or, in some cases, been carted away — since the July 17 downing of the plane.