Singer Neil Diamond is suing his New York neighbours, claiming they are building an illegal structure on their roof that is ruining his views. The SONG SUNG BLUE star has filed papers with the Manhattan Supreme Court against PEGGY and MARIANNE NESTOR. Marianne is the widow of famed designer Oleg Cassini, who died in March (06) at the age of 92. The lawsuit claims Diamond was having renovations done on the roof of his fifth-floor apartment when he noticed the Nestors "had commenced construction of a large copper-clad structure on the roof of the adjacent premises...without obtaining any work permits." The Nestors have also installed "large steel beams as the base for massive air-conditioning units", according to PageSix.com. Diamond contacted city officials for help, but the Nestors ignored inspectors' orders to take the structures down. The star then decided to file a court order to "enforce the zoning law".