Commission spokesman Jean-Christophe Filori told a news conference the EU "strongly deplores" today's verdict by the Ankara state security court. The verdict confirms that Zana and three co-defendants will serve their full 15-year prison sentences.
"The case of Leyla Zana, who was sentenced for nonviolent expression of opinion, gives rise to serious concern in the light of the Copenhagen political criteria [for EU membership] and casts a negative shadow on the implementation of political reforms in Turkey," Filori said.
"Ms. Zana was imprisoned or sentenced for having expressed opinions in a non-violent way. So, for us, she is considered a political prisoner."
The four -- all Kurdish former parliamentarians -- were jailed in 1994 for links to Kurdish rebels.
The commission is due to issue an opinion later this autumn on whether Turkey is ready to start EU entry talks.
Filori today said the court's decision would be "taken into account" in considering Turkey's EU bid. He said entry talks are impossible with a country holding political prisoners, which the European Commission considers Zana to be.
"Ms. Zana was imprisoned or sentenced for having expressed opinions in a non-violent way. So, for us, she is considered a political prisoner," Filori said.
Filori said the EU has asked Turkey to abolish its state security courts, which violate the rights of defendants. He said that Turkey has agreed to "contemplate" this within the context of its ongoing reform package.
Filori went on to note that the use of a state security court in the retrial of Zana is “all the more odd,” as Turkey has accepted that convictions found to be in violation of the European Convention on Human Rights should be retried.
Zana's defense team has launched an immediate appeal. Filori says the commission hopes the appeal will help resolve the case according to what he called "relevant principles of justice."