The United States has warned Russia against stirring separatist sentiment in eastern Ukraine, following unrest in several cities in recent days. U.S. officials said there are clear signs that pro-Russian demonstrations were orchestrated from outside. Meanwhile, recent events in Ukraine have emboldened Russian-speaking separatists in Moldova to renew their calls for independence, with a view of joining the Russian Federation.
Pro-Russian demonstrators in eastern Ukraine and in Moldova are calling for a referendum similar to the one that led to Russia's annexation of Crimea last month.
In the city of Donetsk, rioters stormed the regional government building on Sunday and replaced the Ukrainian flag on the building with a Russian one, while others watched, cheering and chanting "Russia!"
Pro-Russian demonstrations also took place in Kharkiv. Emily Belkina, a mother of three, said Russians in Ukraine want autonomy.
"This new government came to rule with force, you understand, with guns in their hands and we don't have our representative in the new government," said Belkina.
In Washington, State Department spokeswoman Jen Psaki said there is strong evidence that some demonstrators were Russian agents paid to stir unrest. She said Secretary of State John Kerry addressed the issue with Russian Foreign Minister Sergey Lavrov.
"He called on Russia to publicly disavow the activities of separatists, saboteurs and provocateurs, calling for de-escalation and dialogue, and called on all parties to refrain from agitation in Ukraine,” said Psaki.
White House spokesman Jay Carney said Russia continues to increase its pressure on Ukraine.
"We see it in the troops that have massed on the border. We see it in a variety of developments internally within Ukraine, in the regions of the country where there are more ethnic Russians," said Carney.
Russia has said it has no intention of moving farther into Ukraine after taking over Crimea, but its actions have raised concern in other former Soviet republics.
Moldova is afraid of losing its Trans-Dniester region, whose Russian-speaking majority fought an independence war in 1992 and is now renewing its calls for independence, with the idea of ultimately joining the Russian Federation.
Those opposed to Russian influence in Moldova held a demonstration Sunday outside the Russian embassy in the capital, Chisinau.
"We are here to express our resentment against Russian aggression in Moldovan Republic. We do not want the Crimean scenario here. We want our children to have [a] future,” said one protester.
U.S. and European officials will meet in the next 10 days with Russian and Ukrainian officials to discuss how to de-escalate the crisis in Ukraine and discourage Russia from fueling tensions in the region.