DONETSK, Ukraine - Ukraine's future pro-Western president vowed on Wednesday to quickly crush a bloody eastern insurgency even as his country faced a fresh crisis with the looming cutoff of Russian gas.
The ex-Soviet state's industrial hub of Donetsk resembled a ghost town after a devastating two-day firefight with pro-Russian separatists who had seized the local airport left more than 40 rebels dead.
Caught up in the drama were four European civilian observers who were seized at a Donetsk region roadblock apparently set up by the rebels on Monday and had not been heard from since.
European leaders called on Russian President Vladimir Putin to help his smaller western neighbour by using his leverage with the rebels to end a seven-week resistance that has claimed around 200 lives.
But Moscow has thus far failed to reach out to Petro Poroshenko - a 48-year-old billionaire candy maker elected by a resounding margin on Sunday - and cautioned Ukraine that its stepped-up military offensive could only backfire.
Poroshenko told Germany's Bild daily ahead of a visit to Berlin on Wednesday by Prime Minister Arseniy Yatsenyuk that Ukraine had simply run out of options and could no longer put up violence threatening its very existence as a sovereign state.
"We will no longer let these terrorists kidnap people and kill them," said Poroshenko.
"We will end this terror. A real war is being waged against our country."
Some analysts think Kiev has ratcheted up its campaign believing that the 40-point margin of Poroshenko's victory will make it hard for Moscow to question his legitimacy and order its troops to "protect" the east's ethnic Russians.
The Kremlin reaffirmed on Wednesday that it "respected" the will of Ukraine's voters but also denounced the army's "provocative" actions as another step toward strife and discontent.
"We are constantly saying that these provocative military actions are only leading the situation toward a dead end," Kremlin foreign policy adviser Yury Ushakov told the Interfax news agency.
"The president of the Russian Federation is constantly stressing this point."
The million-strong riverside city of Donetsk stood deserted on Wednesday with sporadic reports of gunfire after a devastating two-day battle with more than 100 separatists who had seized the local airport on Monday.