BUCHAREST, Romania (AP) — The management at Romania's main opera house has banned internationally-acclaimed ballerina Alina Cojocaru and Danish ballet dancer and choreographer Johan Kobborg from entering the premises alone, following a conflict with the institution's interim leadership.

In a letter dated April 25 that was sent to the Bucharest National Opera's security department, Cojocaru, Kobborg and seven others can only enter if they are permanently supervised by security, according to a copy obtained Tuesday by The Associated Press.

Deputy Prime Minister Vasile Dancu met with artists Tuesday to try and resolve the conflict, which has seen three shows canceled.

Opera management couldn't be immediately reached for comment. Others on the list are the former interim general manager and former technical director.

Kobborg recently resigned from the opera citing pressure from managers.