Members of the Kurdistan Workers' Party, known by its Kurdish initials PKK, are to begin a phased withdrawal from Turkish territory this week.
More than 4,000 people have died in fighting between the separatist PKK and the Turkish military since the 1980s.
EU Ambassador to Turkey Jean-Maurice Ripert told Turkish newspaper Hurriyet the measure would help with Kurdish cultural and political issues in addition to easing security strains.
"So an agreement by all the citizens of this country on the structure of the state, on identity, language rights and the fight against all kinds of discrimination, is key for the future of this country, and this will tremendously help the accession process of Turkey to the EU," he said.
The withdrawal follows a series of discussions between Turkish government officials and jailed PKK leader Abdullah Ocalan.
Pro-Kurdish leaders said they were concerned about the lack of security guarantees for withdrawing fighters.
The European Union lists the PKK as a terrorist organization.