Amy Winehouse will not perform at the MTV Video Music Awards.The troubled singer - who is currently on holiday with husband Blake Fielder-Civil on the Caribbean island of St. Lucia - was due to sing at the event but her record label, Universal, announced yesterday she will definitely not be taking to the stage. Amy, 23, has also cancelled all her US tour dates, after initially postponing them. Her label said this decision was made "in a continued effort to support Amy's well being."The announcement comes just weeks after the 'Back to Black' singer cancelled her entire 25-date European tour and remaining British festival appearances after overdosing on a cocktail of drugs.The 'Back to Black' singer is up for three MTV awards, including Best New Artist, at the glitzy ceremony which takes place at Las Vegas' Palm Springs Casino Resort on September 9. Amy and Blake, 26, have shocked the world in recent weeks as details of their excessive drug use and turbulent private life have emerged. Last week, disturbing photos of the couple arguing on the streets of London which showed Blake with deep scratches to his face and neck, and a clearly distressed Amy with bandages covering cuts on her arms and blood-soaked feet, thought to be caused by injecting drugs. She later sent a text message to online gossip columnist Perez Hilton claiming she was responsible for the injuries and that Blake had stopped her from self-harming and taking heroin with a prostitute.