Former Foreign Minister of the Czech Republic Karel Schwarzenberg has said that it will be an economic and political mistake for Ukraine to refuse to sign an association agreement with the EU and decide to join the Customs Union instead, he said in an interview with Radio Liberty.

"The requirements of the EU should be fulfilled. All the EU member states went this way and Ukraine cannot be an exception. The failure to do so could be a great tragedy for Ukraine," the politician said.

According to Schwarzenberg, Ukraine must fulfill all EU conditions for the signing of the agreement, including allowing the former Prime Minister of Ukraine Yulia Tymoshenko to travel abroad for medical treatment.

He told Radio Liberty that he hoped that the relevant laws would be adopted by the Verkhovna Rada and Tymoshenko would go to Germany for treatment.

Earlier, Dalia Grybauskaite, the president of Lithuania, which is currently presiding in the European Union, said that the European Union would not sign the association agreement with Ukraine, if the latter did not solve Tymoshenko's issue.