European leaders have mounted renewed diplomatic pressure on Ukraine over its treatment of Yulia Tymoshenko, the jailed former prime minister.
Jose Manuel Barroso, the EU Commission president, said on Tuesday that he would not go to Ukraine during the European football championships in June unless there is a swift improvement in the human rights situation there.
"It is clear that as things stand now, the president has no intention of going to Ukraine,'' Barroso's spokeswoman said.
His announcement followed that of EU Justice Commissioner Viviane Reding, who is also skipping the opening ceremony of the Euro 2012 football tournament, to be hosted by Ukraine and Poland, on June 8.
A German government spokesman also said any visit by Chancellor Angela Merkel during the championship, one of the continent's main sports events, would be linked to Tymoshenko's fate.
Tymoshenko has been on a hunger strike since last week to protest against her alleged beating in prison.
The German government has offered to treat her in Berlin, but Kiev has rejected the offer.
Earlier, Czech President Vaclav Klaus joined German President Joachim Gauck in cancelling participation at a summit of central European presidents in the Ukrainian Black Sea resort of Yalta between May 11-12 over the issue.
'Cold War' tactics
Ukraine dubbed threats by European powers to shun Euro 2012 as a return to Cold War tactics.
"I hope that German statesmen won't reactivate the methods of the Cold War and try to make sports a hostage to politics,'' Oleg Voloshin, the Ukrainian foreign ministry spokesman, was quoted as saying by the Interfax news agency.
Poland has refused to join forces with its fellow EU states.
"We believe that at this point calls for a boycott of the Euro 2012 are totally unfounded,'' Polish government spokesman Marcin Bosacki said. "These two things should not be linked together."
The EU has warned Kiev that its members will not ratify milestone deals on political association and free trade with it as long as Tymoshenko remains in prison.
Ukraine hopes to improve its image and boost tourism by attracting an estimated one million sports fans for the tournament.
Relations between Ukraine and the EU have been strained by the conviction last October of Tymoshenko, the main political rival of President Victor Yanukovych, in a case her supporters say was politically motivated.
Government officials have denied any claims of bias in the case.
Tymoshenko helped lead the 2004 Orange Revolution which doomed Yanukovych's first bid for the presidency.
She has since served twice as prime minister, but lost the 2010 presidential vote to Yanukovych in a close runoff.