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WASHINGTON, March 16 (Reuters) - The United States told Russia on Sunday that it would not accept the results of Crimea's referendum on seceding from Ukraine and urged Moscow to pull its forces in Crimea back to their bases, a senior U.S. State Department official said.
The U.S. official was offering an account of a telephone conversation between Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov, who, according to a Russian statement, "agreed to continue work to find a resolution on Ukraine through a speedy launch of constitutional reform."
The U.S. official made clear Washington was pleased by Moscow's emphasis on constitutional reforms, describing this as "positive." The official stressed, however, that what troubled the United States most were Russian troop movements into Crimea.
"It is Russia's military movements and escalatory steps that are raising the greatest concern," said the official, who spoke on condition of anonymity after Kerry and Lavrov spoke on Sunday, the day of the referendum in Crimea.
"If Russia wants to make a concrete contribution to this process, it will immediately ... pull its forces in Crimea back to bases, end any further military provocations including the exercises to Ukraine's east and south, and work to end the provocative actions of ethnic Russian civilians and irregulars in Ukraine's eastern and southern cities," the official said.
As the referendum in Crimea proceeded, Ukraine accused Russia of pouring its forces into the peninsula, which has a Russian-speaking majority and is home to a Russian naval base.
In his talk with Lavrov, Kerry said Russia must pull back its forces to their bases and raised strong concerns about its military activities in Ukraine's Kherson oblast on Saturday and continuing "provocations" in eastern Ukraine, the official said.
On Saturday, Russian troops landed on a remote spit of land in Kherson Oblast between Crimea and the mainland, Ukrainian defense officials said. Ukraine's border guard said about 60 Russian troops had landed on the strip and begun digging in, assisted by three armored personnel carriers.
It was unclear whether U.S. officials held out much, if any, hope of keeping Crimea in Ukraine, or they were trying to deter Russia from moving into other parts of Ukraine.
"The secretary made clear that this crisis can only be resolved politically and that as Ukrainians take the necessary political measures going forward, Russia must reciprocate by pulling forces back to base, and addressing the tensions and concerns about military engagement," the U.S. official said. (Reporting By Arshad Mohammed; Editing by Bill Trott, Rosalind Russell and Mohammad Zargham)
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