Bulgaria and Bosnia and Herzegovina's prime ministers have urged fans to refrain from violence ahead of a tense UEFA Europa League game between Levski Sofia and Sarajevo in the Bosnia and Herzegovina capital.
"We are true fans also and we urge our friends at the stadium in Sarajevo: Do not ruin the game! Leave the rivalry to the players and do not insult or humiliate the other fans," a joint statement from Boyko Borisov and Vjekoslav Bevanda read on Wednesday.
Sarajevo and Levski Sofia will face each other on Thursday evening (Friday morning AEST) in a second-leg match of the Europa League's second-qualifying round.
The Bulgarian team won the first leg 1-0 in Sofia but the match was marred by provocative chants from the crowd that sparked angry calls for revenge among the Bosnia and Herzegovina side's fans.
UEFA Europa League
UEFA has confirmed that the winners of the Europa League will earn a place in the Champions League from 2015.