Sergei Polunin blames unspecified 'health issue' for walking out of Midnight Express Ballet dancer Sergei Polunin has apologised for walking out on a production of Midnight Express days before it opened blaming an unspecified "health issue" for his exit. The star, who hit the headlines when he unexpectedly quit the Royal Ballet last year, joked that he was "pretty certain" he would make it to the stage for his new show - Coppelia at the Coliseum in the West End in July. He walked out of Midnight Express with Peter Schaufuss's company in April before its London premiere. Speaking at a press conference today, Polunin said: "The only thing I can say is there was a health issue and I couldn't say anything at that time." He added: "I apologise to the audience because I couldn't even explain at that time." Asked if he could explain now, he said: "Not yet, maybe one day I will." Polunin, who has performed in Russia since April, said: "In Russia it's great because you can concentrate 100 per cent on your work. There are not as many distractions as London or in the West. Schaufuss said he was "delighted" Polunin was coming back to the London stage and described him as a great dancer. Asked if the pair had made up, Polunin said he was not "friends" with Schaufuss, but said they had a professional relationship. He said: "I always respect Peter as a dancer and as a director, we've never made friends, but I still respect him. I think it's important for professionals to do work even if you don't become friends. Asked about his reputation as the bad boy of ballet, Polunin said: "It's not being bad, it's just trying to find yourself."