The European Union and Ukraine are gathering in Brussels to initial an association agreement, with the bloc still refraining from finalizing the pact over objections to the jailing of former Prime Minister Yulia Tymoshenko.
Tymoshenko is seen by the EU, other Western governments, and many defenders at home as a victim of persecution by her political rivals.
The association agreement sets out the terms of deeper political and economic integration between the EU and Ukraine, but it falls short of making Ukraine an official candidate for EU membership. It has been the subject of negotiations between the EU and Ukraine since 2007.
"The initialing of the EU-Ukraine association agreement, is really the first, technical, procedural step," Peter Stano, a spokesman for EU Enlargement Commissioner Stefan Fuele, told RFE/RL. "The more important steps which carry real value for this association agreement to enter into force will be signature and ratification. But, as I said, these steps depend on the performance of Ukraine in the areas of rule of law and judiciary."
Brussels and Kyiv had hoped to fully sign and implement the association agreement at the end of last year. But the sentencing of Tymoshenko in October to seven years in jail for alleged abuse of authority in connection with gas contracts she agreed to with Russia in 2009, sparked a fresh crisis in ties. Ukrainian authorities are continuing to pursue other criminal charges against her.
"We have concerns about the perceived selective use of justice in imprisoning the political opponents," Stano told RFE/RL. "These are the issues which we will be looking into as the EU commission and as EU member states in order to find out whether the time is right for signature of the [EU-Ukraine] association agreement."
The association agreement does not contain an EU membership perspective for Ukraine -- though it defines Ukraine as "a European country with European identity" and acknowledges the "European aspirations of Ukraine."
Ukrainian authorities deny a political motive in prosecuting Tymoshenko, the former Orange Revolution heroine who unsuccessfully sought the presidency in a hard-fought campaign against current President Viktor Yanukovych in 2010.
The EU has demanded Tymoshenko's release, and says she should be able to run in Ukraine's next general election in October.
However, on March 29, Ukrainian authorities announced that Tymoshenko will soon face another trial in connection with alleged tax evasion in the mid-1990s.
It is expected that after the association agreement is officially signed, it could take up to three more years for it to be ratified and implemented by all of the current 27 EU member states plus Croatia, which is due to join the bloc next year.
As talks between the EU and Ukraine have continued, Russia, Ukraine's giant neighbor to the east, has been trying to secure Kyiv's loyalty by integrating Ukraine into economic and political structures that Moscow has helped create in recent years, such as the Eurasian Economic Community. Kyiv has so far declined to fully dedicate itself to such initatives.
Speaking at a conference in Kyiv on March 30, President Yanukovych said Ukraine should increase its cooperation with the countries of what he called "the Eurasian region" while also maintaining its path toward integration with Europe.
With reporting by AFP and AP