The EU supports sanctions while laundering billions in dirty money from Russia.
Putin's seizure of Crimea and his war in the Donbas have fostered a patriotism that is driving Ukraine toward the EU.
Exclusive: Ukraine's president explains why his country must give more power to regional governments.
Putin-backed forces appear to be trying to encircle the city, which stands on the road to Crimea.
Clashes near the port city of Mariupol and the rebel-held town of Gorlivka have put further strain on a fragile ceasefire.
Combined Russian-separatist forces have withdrawn from Shyrokyne. But Mariupol residents remain wary.
Moscow is not expecting NATO forces to intervene if it grabs Mariupol.
Mariupol is on the road to Crimea, but taking the city is far beyond the rebels' reach without Putin's troops.
U.S. and Ukrainian official have both reported that both Russian troops and weaponry are gathering on the border.
The port city is considered a prime target for the Donetsk separatists.
Radical views and the use of symbols echoing Nazi emblems have caused alarm in the West and Russia.
Despite Poroshenko's insistence that weaponry is being withdrawn from the frontline, tensions are still running high.
Law student Alik Sardarian tended to the injured during the Maidan uprising before reluctantly going to war.
The ceasefire agreed in Minsk last week is now on the brink of total collapse as the rebels advance on Mariupol.
Ukrainian military fear that Mariupol is next target for pro-Russian separatists.
Violence in Ukraine's eastern Donbass regions is at its worst since the September ceasefire agreement
In Mariupol, Poroshenko promised 'crushing defeat' to Russian separatists if they violate ceasefire agreement