European Council President Herman Van Rompuy and European Commission President Jose Manuel Barroso have called on the Ukrainian authorities to resolve the remaining issues, including the situation with former Ukrainian Prime Minister Yulia Tymoshenko, in order to ensure the signing of the Association Agreement at the Eastern Partnership summit in Vilnius.

They said this at a press conference in Brussels on Friday after the EU summit.

"We hope to take important, even historic steps, in particular, with Ukraine, provided there is determined action and tangible progress," Rompuy said.

"The Association Agreement will be a test for the Eastern Partnership as a whole. The Ukrainian leadership knows what has to be done."

When asked to comment on the situation with Tymoshenko, he reaffirmed the position of Brussels that "we need a decision on this issue."

In this regard, he called on the Ukrainian authorities to find a solution to this issue, along with the mission of former Presidents Pat Cox and Aleksander Kwasniewski, because "it is the best way to solve problems, which help make it possible to sign the Association Agreement."

Barroso, in turn, said that the signing of the Association Agreement could be "a truly historic event."

He reminded the audience that the EU leaders had met several times with Ukrainian President Viktor Yanukovych and clearly demonstrated that "we will stick to our commitments if Ukraine also sticks to what it has committed to do."

He also confirmed that Ukraine still needs to find a suitable solution to the Tymoshenko case.