One of the youngest dancers ever to be a principal of the Royal Ballet, Ukrainian Sergei Polunin, has quit just days before a new production opens and only two years after he was promoted. \"This has obviously come as a huge shock,\" said Monica Mason, the director of the Royal Ballet, in a statement issued late Tuesday. \"Sergei is a wonderful dancer and I have enjoyed watching him tremendously, both on stage and in the studio, over the past few years. I wish him every success in the future.\" Polunin joined the Royal Ballet in 2007 from the Royal Ballet School and was promoted to principal at the end of the 2009-10 season when he was only 19, making him the youngest male dancer to make the top job. The 21-year-old was due to take the lead in Mendelssohn\'s \"The Dream\" at London\'s Royal Opera House on February 1, and his name was still on the cast list Wednesday. A spokeswoman for the opera house said his replacement would be announced shortly, and media reports said Australian Steven McRae would take his place. In a Twitter message on Tuesday, Polunin appeared keen to leave, writing: \"Just have to go through one night!!! then will make my next moves\". According to the Daily Telegraph, he has previously spoken of wanting \"a life outside ballet\" and suggested opening a tattoo parlour.