A unit of Lloyds of London, which insured Michael Jackson’s canceled comeback concerts in London two years ago, has filed suit to nullify a $17.5 million policy taken out by promoter Anschutz Entertainment Group.

Lloyd’s underwriter Cathedral Capital Ltd. claims in its Los Angeles Superior Court lawsuit that an insurance policy taken out to cover the cancellation or postponement of the concerts in the case of death, accident or illness had been voided by Jackson’s undisclosed drug use.

Jackson, 50, died on June 25, 2009 in Los Angeles as he was rehearsing. He was found to have taken a massive dose of the anesthetic propofol and a cocktail of other sedatives and painkillers administered by his doctor, Conrad Murray.

The lawsuit, filed Monday, claims that Los Angeles-based AEG failed to disclose the singer’s medical history, “including, but not limited to, his apparent prescription drug use and/or drug addiction,” according to the Reuters news service. Cathedral also claims that AEG has not cooperated in its investigation of the claim against the policy.

AEG, which had hired Murray, has not commented on the lawsuit.

Murray is scheduled to stand trial in September in connection with the overdose. He has been charged with involuntary manslaughter.