Russia has warned the Ukrainian government to pull its military from the restive southeast of its own territory, saying it could invade to "protect" pro-Russian separatists there – just as it did in Georgia, another former Soviet republic that Moscow invaded six years ago.
In an interview with the Kremlin-owned RT (Russia Today) television station, Foreign Minister Sergei Lavrov for the first time compared the situation in Ukraine's Donbass region – where pro-Russian gunmen have seized control of strategic locations in at least 10 cities – to South Ossetia, a breakaway region of Georgia. Russia invaded parts of Georgia following an exchange of fire between Georgian and South Ossetian troops in August, 2008. That war lasted just six days, ending in humiliating defeat for the Georgian army and solidifying South Ossetia's de facto independence from Tbilisi.
Mr. Lavrov's warning of war came less than 24 hours after Ukraine's Interim President Oleksandr Turchynov ordered his army to resume a stalled effort to oust the pro-Russian separatists from seized police stations and government offices around Donbass.
"If we are attacked, we would certainly respond. If our interests, our legitimate interests, the interests of Russians have been attacked directly, like they were in South Ossetia for example, I do not see any other way but to respond in accordance with international law," Mr. Lavrov said. "Russian citizens being attacked is an attack against the Russian Federation."
It's unknown how many residents of the coal-producing Donbass region – which is predominantly Russian-speaking – carry Russian passports. On Monday, President Vladimir Putin signed a new law making it easier for Russian-speaking citizens of the former Soviet Union to apply for Russian citizenship.
Russia's Foreign Ministry later issued a statement demanding "the withdrawal of Ukrainian army units" from southeastern Ukraine. Ukraine responded by demanding that Russia withdraw the tens of thousands of troops it has massed on its side of the shared border between the two countries. Those troops held fresh military exercises Wednesday, according to Russian media.
Ukraine also alleges that some of the militants participating in the Donbass uprising are masked Russian military intelligence officers, a charge Moscow denies.
The increasingly aggressive line from the Kremlin has also rattled Russia's other neighbours. On Wednesday, 150 U.S. paratroopers arrived in Poland. Similar size contingents are headed to the Baltic states of Estonia, Latvia and Lithuania in the coming days, a rapid response force meant to indicate that the NATO military alliance would defend its members from any aggression. Latvia and Estonia, in particular, have large Russian-speaking populations.
"It's a gesture, a small one, but an important one," said Adam Eberhardt, deputy director of the Centre for Eastern Studies, a Warsaw think tank funded by the Polish government. "There's a feeling that if Russia is not stopped in Ukraine, it may try to destabilize Latvia and Estonia in the future."
Foreign Minister John Baird arrived Wednesday in Warsaw ahead of meetings here with Polish officials, part of a trip that will later take him to Latvia and Estonia. Canada announced last week that it will deploy six CF-18 fighter jets to Poland "to enhance the readiness of NATO allies" as tensions with Russia grow.
Despite the ramped-up rhetoric, there were few signs Wednesday of the renewed Ukrainian military operation in Donbass. The Interior Ministry claimed its troops had "liberated" the town of Svyatogorsk, but reporters there said residents claimed they had never been under rebel occupation. Ukrainian military vehicles were filmed in the city of Izyum, just outside the Donbass area.
Adding to the Cold War feel of the Ukraine conflict, Mr. Lavrov accused the United States of making decisions on behalf of the government in Kiev. He noted that the announcement to relaunch the military operation in Donbass came shortly after Mr. Turchynov hosted U.S. Vice-President Joe Biden.
"It's quite telling that they chose the moment of the Vice-President of the United States' [visit] to announce the resumption of this operation," Mr. Lavrov said. "I don't have any reasons not to believe that the Americans are running the show in a very close way."
Russia and the West have been sharply at odds ever since a February revolt in Kiev that saw the Moscow-backed government of Viktor Yanukovych overthrown by protesters demanding better ties with the European Union, as well as an end to runaway corruption.
Russia claims the revolt was in fact a Western-backed coup, and moved quickly in its wake to seize and annex the Crimean Peninsula, in the south of the country. The Ukrainian government accuses Moscow of aspiring to repeat the Crimea takeover in the Donbass region.
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