President Petro Poroshenko has proclaimed an end to the "most dangerous" part of Ukraine's pro-Russian uprising and the start of a post-war recovery that would lead to an EU membership bid in 2020.
But the upbeat message on Thursday was clouded by new deadly clashes and a defiant decision by guerrillas to hold independent elections on November 2 that Poroshenko said he hoped Russia would not recognise.
Fresh negotiations in a politically-charged energy price dispute will take place in Berlin on Friday between Russia, Ukraine and the European Commission.
Russia suspended deliveries to Ukraine in June due to a price dispute, threatening supplies to some European consumers.
The row, along with the escalating costs of war and the shutdown of giant industries in the east, have only accelerated Ukraine's economic implosion.
Pro-Western leader Poroshenko told the first press conference since his June inauguration that he would never allow a resurgent Kremlin and gunmen entrenched in Ukraine's eastern rust belt to halt Kiev's ambition to break out of Russia's embrace.
"We suffered for too long in the socialist camp to let someone lower an iron curtain across our western border," Poroshenko said in reference to Ukraine's Soviet past.
"I have no doubt that the biggest, most dangerous part of the war is already behind us thanks to the heroism of Ukrainian soldiers." The five-month conflict has killed more than 3,200 people and driven 650,000 from their homes across a bomb-scarred region that once served as the country's economic driving engine.
Poroshenko showed he was determined to continue on a Westward path as he unveiled a comprehensive package of social and economic reforms, dubbed Strategy 2020, which he said "will prepare Ukraine to apply for membership in the European Union in six years".
The plunge in relations between Moscow and Kiev came after the February ouster of a Moscow-backed leader, followed by the Kremlin's annexation of Crimea and its alleged backing of a bloody pro-Russian revolt.
An unexpected militia counter-offensive at the end of last month was only halted when Poroshenko agreed to a truce the Kremlin helped partially draft.
The plan called for rebel-held regions to hold local council elections on December 7 to help restore law and order.
But separatist leaders soon objected because it gave them only limited self-rule for three years. They now plan to form their own "Supreme Soviet" parliament and elect a formal government.