A senior EU envoy has warned Ukraine not to miss its chance to sign a key deal with the bloc at a Vilnius summit on November 28-29.
Aleksander Kwasniewski was speaking one day after Ukraine's parliament failed to agree on a bill that would have allowed imprisoned former Prime Minister Yulia Tymoshenko to seek medical treatment abroad.
"Failure to sign in Vilnius would mean the postponing of the agreement for an indefinite number of years," Kwasniewski told the Ukrainian news agency UNIAN.
The EU considers Tymoshenko's conviction for abuse of office to have been politically motivated and has made her release a prerequisite for Kyiv to clinch an Association Agreement -- a first step toward eventual EU membership.
Kwasniewski also warned that Russia was "making a mistake" by trying to prevent Ukraine from signing the agreement. Moscow wants Ukraine to join its customs union with Belarus and Kazakhstan.
The Ukrainian parliament is due to discuss legislation that would allow Tymoshenko to travel abroad for treatment on November 19. Kwasniewski and former European Parliament President Pat Cox, who together have been monitoring Ukraine ahead of the Vilnus summit, plan to travel to Kyiv for the parliamentary debate.
President Viktor Yanukovych said on November 14 he would only sign a law that could not be abused to evade criminal responsibility -- suggesting Tymoshenko would be expected to return to Ukraine after treatment and continue serving her sentence.
Opposition supporters have already rejected this option.
In Ukraine, meanwhile, Vitali Klitschko, the leader of the opposition Ukrainian Democratic Alliance for Reforms, has again reiterated his plans to run for president in 2015.
Talking to RFE/RL on November 14, Klitschko, a former world boxing champion, said: "We can all knock [Yanukovych] out and we will do everything to do this. In 2015 at the presidential election, President Yanukovych will be knocked out. And the knockout will be the end of his political activity."
Klitschko urged supporters to attend a pro-EU rally in Kyiv on November 24.
He said that "all people of Ukraine regardless of their political views" should come to the opposition-organized event, and he urged supporters planning to attend the rally to bring Ukrainian national flags and EU flags instead of political banners.
Ukraine's opposition said on November 13 it was planning the rally to urge parliament to adopt a package of laws, including the one allowing Tymoshenko to receive medical treatment in Germany.
With reporting by AFP, UNIAN, and RFE/RL's Ukrainian Service