Ukraine warned that its "all-out" assault on pro-Russian insurgents may last another month and rejected calls for a ceasefire as it pushed tanks within striking distance of the rebels' two remaining strongholds, on Thursday.
An AFP team about 20 kilometres south of the eastern hub of Donetsk - a million-strong city to which most of the militias have retreated since the weekend -- saw heavy armoured vehicles fan out across the rolling corn and sunflower fields of the economically-vital rustbelt.
An earthmover's engine stuttered in the stifling heat as it dug trenches to help troops dodge artillery strikes from thousands of insurgents who are refusing to give up their bloody three-month drive to join Russian rule.
"We arrived here last night," said a balaclava-wearing soldier named Yuriy as his comrades stretched electric cables to a nearby farm to power up their equipment.
AFP reporters 30 kilometres west of Donetsk also heard echoes of heavy artillery fire around the town of Korlivka, held by the separatists since early April with the alleged help of Russian financial and military support.
The interior ministry added to the confident new tone resonating throughout Kiev by reporting the launch of "an all-out attack... across several parts of the front".
But what may have looked like bravado just a few weeks ago seemed to the bearing out the streets of eastern industrial cities that were once the economic driving engine of both the Soviet Union and Ukraine but now resemble half-gutted ghost towns.
Donetsk separatist "prime minister" Oleksandr Borodai admitted that he was on the verge of ordering a partial evacuation of the city because his men had still not received the additional shipments of heavy arms they had urgently sought from Moscow.
"Russia must be ready to receive several hundred thousands refugees," he told reporters.
Ukrainian interior ministry adviser Stanislav Rechinsky announced on state television that it looked like the last of the eastern insurgency would be crush "within a month".
Rechinsky added "there will be no air or artillery strikes" against Donetsk or its neighbouring rebel hub of Lugansk because of the toll in the low-scale war had already claimed more than 500 lives.
The Ukrainian health ministry said its earlier report of 478 civilians deaths in the eastern offensive was issued in error because it included those who had passed away from natural causes.
No talks with 'terrorists'
Fears of a civil war breaking out on the EU's easter frontier have redoubled European efforts to force Kiev to negotiate truce terms that could help calm the most explosive East-West standoff since the Cold War.
The tide in the conflict turned Saturday when insurgents abandoned their Slavyansk bastion -- a city of 120,000 now emptied of half its population and in dire need of fresh water and medical supplies.
Kiev paints the insurgency as a proxy war being waged by Russian President Vladimir Putin in reprisal for the February ouster of an allied administration and the collapse of his dream to push Ukraine into a powerful new post-Soviet bloc.
But Kiev's recent string of military successes have alarmed European leaders who are hoping to secure a truce to take pressure off the bloc from adopting further economic sanctions that might damage its strong energy and financial ties with Russia.
EU leaders resisted Washington's calls to be firmer with Putin and on Wednesday only promised to add 11 new names to its list of 61 Russians and Ukrainian separatists targeted by travel and financial bans.
Moscow has shrugged off such measures and Russia's wobbly stock market has rebounded in the belief that Europe was too concerned about its own economy to unleash meaningful punitive steps.
'Skype talks' with rebels
Western-backed President Petro Poroshenko this week said talks with rebel commanders -- demanded on a nearly-daily basis by Putin and his top ministers -- were impossible because they had gone into hiding in Moscow.
But the new Kiev leaders have also been keen to avoid drawing the ire of EU leaders whose political and financial backing is vital to their survival in the face of the Russian threat.
Ukrainian Foreign Minister Pavlo Klimkin on Thursday for the first time suggested contacting the militia leaders by videoconference.
"We live in a modern world. Why not start our negotiations by videoconference using Skype?" Klimkin asked.