The authorities in Ukraine have condemned calls for a boycott of this summer's Euro 2012 Championships over the alleged mistreatment of former prime minister Yulia Tymoshenko.

Ms Tymoshenko was jailed for seven years last October.

Ukraine - which is co-hosting Euro 2012 with Poland - has denied mistreating Ms Tymoshenko, who is reported to be on hunger strike, and has described calls for a boycott as a return to Cold War tactics.

President of the EU Commission José Manuel Barroso is among those who have said they will not attend the tournament.

A spokesman for German Chancellor Angela Merkel has said she is considering her position on the issue.

Ukraine described the possible boycott by EU leaders of the Euro 2012 football games it hosts as "artificial manipulation" that showed disrespect for sport.

"Sport is sport and politics is politics. All of this is nothing but artificial manipulation," foreign ministry spokesman Oleg Voloshyn told AFP.

He stressed that Ukraine had not yet formally extended invitations to any EU leaders and argued that "the boycott would touch not the Ukrainian authorities but the football championship".

Meanwhile, Ukraine has given a "clear assurance" to UEFA that steps are being taken to ensure the safety of visitors following a series of blasts in Dnipropetrovsk on Friday.

"The security situation around the tournament, and in particular in Ukraine following the recent events in Dnipropetrovsk, was thoroughly reviewed," UEFA said in a statement yesterday following a meeting with members of the local organising committee.

"UEFA received a clear assurance by the governments of the host countries that all necessary steps are being taken to guarantee the safety of all visitors, from fans to participating players."

30 people were injured on Friday when four bombs planted in rubbish bins in various downtown locations of Dnipropetrovsk exploded at short intervals in the city of 1.3 million in what prosecutors said was an "act of terrorism".

UEFA also briefly referred to the political situation in Ukraine.

"UEFA alerted the Ukrainian delegation about the concerns raised by the political situation in Ukraine among European politicians and media," said UEFA.

"Even though UEFA, as a sports organisation, never interferes in political matters, UEFA has asked the Ukrainian delegation to convey these concerns to the competent authorities."

A court ruled Ms Tymoshenko exceeded her powers as prime minister when forcing through a 2009 gas deal with Russia. Her supporters allege the charges were politically motivated.