Ukraine's embattled premier yesterday vowed to give more powers to the regions in an effort to stamp out a separatist insurgency, as a gas war with Russia threatened European supplies.
Prime Minister Arseniy Yatsenyuk's promise during an unannounced visit to the blue-collar coal mining region of Donetsk came as militants armed with Kalashnikovs barricaded themselves inside the local administration building and demanded a referendum on joining Russia.
A similar occupation of the state security office of the hardscrabble eastern city of Lugansk has confronted the untested leaders with their biggest challenge since their February ousting of a Kremlin-backed president and decision to strike an alliance with the West.
But Russian President Vladimir Putin - his troops already massed along Ukraine's eastern frontier following their seizure of Crimea - only upped the stakes on Thursday by threatening to cut off Ukraine's gas over unpaid bills.
That could limit the supplies of at least 18 European nations for the third time since 2006. Each of the previous interruptions also coincided with attempts by Kiev to pull itself out of the Kremlin's historic sphere of influence.
Russia has already increased the price it charges Ukraine for gas by 81 per cent and demanded the country rewrite its constitution to give eastern regions the right to set their own economic and diplomatic relations with Moscow.
The Kremlin's emphatic response to its possible loss of control over the neighbouring nation of 46 million has plunged its relations with the West to post-cold war lows and forced Nato to boost the defence of former Soviet satellite states.
But Yatsenyuk was more preoccupied yesterday with trying to end a five-day siege by pro-Kremlin militants who have seized strategic buildings and exposed Kiev's limited sway over the heavily industrialised east.
He flew overnight to Donetsk to enlist the help of its mayor and Rinat Akhmetov - Ukraine's richest man - in finding a bloodless solution to the militants' occupation of the local government seat.
Yatsenyuk immediately addressed one of the protesters' most pressing concerns by promising never to limit the use of Russian in the region.
"No one under any circumstances will restrict the use of a language that a person is accustomed to using," Yatsenyuk told local officials.
He also admitted that he "must respond to people's desire to have more regional authority". "We will implement this task within the framework of constitutional reforms," he said.
Kiev has previously said it was ready to grant more powers to the regions, while stopping well short of creating the federation sought by Russia.
Akhmetov for his part warned Yatsenyuk against any use of force to dislodge the militants - a possibility raised by the Ukrainian interior minister earlier in the week. "I am against bloodshed," the tycoon told Yatsenyuk. "The only right path is through negotiations."