Fuele told the European Parliament on March 13 that Ukraine's leaders expressed their "unequivocal commitment" to addressing democratic shortcomings and concerns over selective justice at a recent EU-Ukraine summit.
However, Fuele said a "number of developments" are contrary to that commitment.
In particular, he cited concerns over Kyiv's recent decision to strip the lawyer of jailed opposition leader and former Prime Minister Yulia Tymoshenko of his parliamentary seat, a move that has prompted the opposition to block the work of parliament, the Verkhovna Rada.
Kyiv hopes that the agreement, the first of its kind between the EU and an eastern neighbor, will be signed in November at an Eastern Partnership summit in Lithuania.
The United States this month expressed similar concern over recent moves in the Ukrainian parliament to remove lawmakers.