EU Commissioner for European Neighborhood Policy Johannes Hahn expects that constitutional reform in Ukraine will be completed this fall.

"The constitutional reform should be completed already by this fall. There should also be a reform of public administration, and an extremely important issue that has been raised and will continue to be raised during all sections of the current Yalta meeting is the issue of combating and preventing corruption," he said at a joint briefing with Ukraine's President Petro Poroshenko in Kyiv on Friday.

Hahn congratulated Ukraine on voting for the amendments to the Constitution and expressed the hope that after the recent "the outbreak of violence," that further processes will take place peacefully.

Decentralization is the key to further democratic transformation of the country, modernization, and the improvement of the governance system, he said.