Stefan Fule, the European Union's commissioner for neighborhood policy, addressed Ukrainian delegates Friday in Yalta.
A possible association agreement between the EU and Ukraine is on the agenda for a November meeting in Vilnius, Lithuania. Lithuania holds the rotating presidency of the EU. Fule said he's seen remarkable progress from Ukrainian leaders on political reforms needed to move closer to the EU.
"Time is not on our side but we are on a good track," he said.
Former Prime Minister Yulia Tymoshenko, in prison on charges of abusing her position of power, sent a letter to the Yalta conference expressing support for the relationship.
"If the conditions for a consistent and effective implementation of the agreement are not created, it can, unfortunately, turn into another lost opportunity," she warned.
Fule said he's seen a growing level of coordination between ruling and opposition figures in the Ukrainian parliament.
"I hope very much that this is a promise for the future and that the European agenda will always stay above party interests as it reflects the strategic interests of this country," he said.
The EU had expressed concern about selective justice in Ukraine.