Russian President Vladimir Putin said he has "a right" to send troops into Ukraine but hopes he will "not have to exercise that right."
Speaking live on Russian TV call-in show after a clash in eastern Ukraine in which three pro-Russian protesters were reported killed, Putin warned the Ukrainian authorities of "the abyss they're heading into" and urged dialogue.
He also admitted for the first time that Russian forces had been active in Crimea, which was annexed by Moscow last month. Previously he insisted that the camouflaged, masked gunmen who took over Crimea were a local "self-defense" force.
But Putin stopped short of saying Russian forces were currently operating in eastern Ukraine.
"It’s nonsense," Putin said. "There are no Russian troops or special forces in eastern Ukraine," adding that Kyiv’s use of armed force in the region is a "serious crime."
The Russian president harshly criticized the West for trying to get Ukraine to align with it and said that people in eastern Ukraine have risen against the authorities in Kyiv, who ignored their rights and legitimate demands.
He said Russia has no interest in reviving Cold War-era divisions, even if Moscow felt threatened by NATO's eastward expansion and was angered by U.S. interventions in Iraq, Libya and Syria that had gone ahead over the Kremlin's objections.
"The Iron Curtain is a Soviet invention,'' Putin said during the call-in show, which lasted just short of four hours. "We have no intention of closing off our country and our society from anyone.''
Ukrainian presidential election
He also said he will not recognize the results of Ukraine's upcoming elections on May 25.
The elections violate Ukraine’s constitution, as Viktor Yanukovyh is still legally president, Putin said.
Ukraine's prime minister on Thursday accused Putin of trying to sabotage the election and said Moscow was responsible for deaths in recent clashes in eastern Ukraine.
"Russia is playing only one game: further aggravation, further provocation, because the task, that Putin today officially announced, is to wreck the presidential election on May 25," Arseny Yatseniuk told journalists in Kiev.
The crisis has alarmed Russia's neighbours, which fear Russia may not stop at Crimea and may seek to grab back further chunks of former Soviet territory.
In comments likely to heighten such concerns, Putin said the people of Transdniestria - a breakaway, Slav-dominated region of ex-Soviet Moldova - should have the right to decide their own fate, though he stressed the need for negotiations.
Putin is also requesting advance payments for gas shipped to Ukraine in one month if it fails to reach agreement on settling its debts, urging Europe to assist Ukraine.
"What is the current number-one problem? It is that Russia can't carry this burden [of helping Ukraine struggle through crisis] single-handed," Putin said. "It is for this reason that we have suggested to our European partners and friends that all of us meet as soon as possible and map out methods of support for the Ukrainian economy. That is, of course, if you truly care about the well being of Ukraine, and truly love the Ukrainian nation."
Putin added that it would not be possible for Europe, which is trying to cut its reliance on Russian energy, to completely stop buying Russian gas. Russia meets presently around 30 percent of Europe's natural gas needs.
He said that the transit via Ukraine is the most dangerous element in Europe's gas supply system, and that he was hopeful a deal could be reached with Ukraine on gas supplies.
He also expressed hope for the success of Thursday's talks in Geneva that brings together the United States, the European Union, Russia and Ukraine for the first time since the Ukrainian crisis erupted.
"I think the start of today's talks is very important," he said, "as it's very important now to think together about how to overcome this situation and offer a real dialogue to the people."
Obama administration officials played down any expectations that the meetings in Geneva would yield a breakthrough or Russian concessions meaningful enough to avoid new U.S. penalties. With Ukraine struggling to contain a pro-Russian uprising in its eastern region bordering Russia, the Obama administration is preparing additional sanctions against Moscow and a boost in aid for the Ukrainian military in the coming days, U.S. officials said Wednesday.
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