In Donetsk, a self-appointed "People's Council" declared an independent republic in the traditional coal-mining center, announced plans to hold a Crimea-style referendum on joining Russia on May 11, and appealed to the Kremlin to send a "temporary" Russian peacekeeping force to protect them from retaliation by the interim authorities in Kiev.
An administration building in Kharkiv, occupied by pro-Russian protesters Sunday, was retaken by police Monday. In Luhansk, protesters throwing stun grenades and Molotov cocktails took over the local headquarters of Ukraine's security service, and reportedly raided the station's weapons store.
There has been sporadic turmoil since the government of former President Viktor Yanukovych – who had been democratically elected with the support of eastern voters – was deposed in February by nationalist-minded protesters with a power base in the country's west. But the current uprisings in the eastern regions, which experts say almost certainly took place in coordination with Moscow, raise serious questions about the Kremlin's plans for the heavily-industrialized, Russia-oriented eastern and southern regions of Ukraine.
Acting Prime Minister Arseniy Yatseniuk told journalists in Kiev that the protests were part of a Russian plan to undermine Ukraine. "The plan is to destabilize the situation, the plan is for foreign troops to cross the border and seize the country's territory, which we will not allow," he is quoted as saying.
The Russian Foreign Ministry dismissed Kiev's criticism. "Enough of blaming Russia for all of Ukraine's current troubles," it said in a statement, adding that without serious constitutional reform, as proposed by Russia, Ukraine's ongoing stability is unlikely. "If the irresponsible attitude by those who call themselves the Ukrainian authorities toward the fate of their own people continues, then these challenges and crises will inevitably continue to crop up in Ukraine."
The events in eastern Ukraine "show that Russia is not going to give Kiev any breathing space, and certainly not going to allow the [planned] May 25 elections to take place, because that would restore legitimacy to the government in Kiev," says Sergei Strokan, foreign affairs columnist with the Moscow daily Kommersant.
"But it's not clear what the endgame is here. If you'd asked me a month ago, I wouldn't have thought Russia would annex Crimea. But it did, and it happened very rapidly. So now it's impossible to say what might occur next. I think the Kremlin wants to keep all options on the table," he adds.
Following the annexation of Russian-majority Crimea last month, Moscow published a road map for a negotiated settlement between Russia and the West, including sweeping constitutional reform that would decentralize power and allow regions to go their own way on economic choices and even international associations. Moscow has not spelled out details of the decentralization plan, referred to as "federalization," but it would probably end any project of building a unified, independent Ukraine.
Russian President Vladimir Putin insisted after absorbing Crimea that there were no further plans to dismember Ukraine. But a Russian parliamentary declaration granting Mr. Putin full rights to use Russian troops on the territory of Ukraine remains in full force.
Sergei Markov, a Kremlin-connected analyst who's spent much of the past month in Crimea advising the new authorities there, says Russia's plan is still to get Washington to agree with Moscow on the main points of the road map, including the federalization of Ukraine. Moscow will not discuss it directly with Ukrainian authorities because, he says, "if I was bitten by a dog in the park, would I want to negotiate with the dog? No, I want to talk with its owner."
Mr. Markov says Plan A is still to help Ukrainians "rebuild their democracy" so that the rights of Russian-speakers, and their geopolitical preferences, will be permanently protected. He says the situation in eastern Ukraine is different from Crimea, but he adds that everything depends on whether the US will sit down and work out an agreement with Russia about Ukraine's future.
Mr. Strokan says that Ukraine's eastern regions have one key difference from Crimea: Support for straight-out reunification with Russia is substantially lower. "Of course majorities speak Russian, and they may be sort of pro-Russian, but only a minority – maybe a third – actually feel like joining Russia," he says. "If a referendum takes place, it would not have Crimea-like results and there's no guarantee it would win at all."