KIEV - The Ukrainian and European parliaments on Tuesday simultaneously ratified a landmark pact at the heart of the ex-Soviet country's bloodiest crisis since independence.
The vote on an accord that decisively steers Ukraine towards the West came just moments after parliament agreed to offer limited self-rule to the pro-Russian east to try to end a bloody five-month separatists uprising.
But renewed deadly fighting in the east has heaped further pressure on a fragile truce, and raised new questions about whether President Petro Poroshenko will succeed in keeping his splintered country together.
Poroshenko said the adoption of the 1,200-page cooperation agreement with the European Union was Ukraine's first step towards membership of the 28-nation bloc.
"Tell me, who will now dare to shut Ukraine's doors to Europe?" the pro-Western leader said.
"Who will be against our future membership of the EU, towards which today we are taking our first but very decisive step?"
Lawmakers rose for a rousing rendition of the national anthem sung with their right hands solemnly placed on their hearts. European MPs in Strasbourg also all stood and cheered.
But the historic occasion was muted by the two sides' decision to bow to Russian pressure and delay until 2016 the implementation of a free trade deal that would pull Ukraine out of a rival union being built by the Kremlin.
The rejection of the same EU association agreement deal by Kremlin-backed president Viktor Yanukovych in November triggered the bloody chain of events that led to his February ouster and Russia's subsequent seizure of Ukraine's Crimea peninsula.
The decision by Kiev's new pro-Western leaders to still strike the agreement saw Moscow cut off gas supplies and allegedly orchestrate a separatist revolt in the industrial east that has now claimed more than 2,700 lives.
Russia's denials of involvement have not spared it from waves of punishing Western sanctions that have left President Vladimir Putin more isolated and acting less predictably than at any stage of his dominant 15-year reign.
But a European-mediated truce Kiev and Moscow clinched on September 5 has offered the first significant glimmer of hope that the crisis may at last be abating and allowing East-West tensions to mend.