Katherine Heigl is contractually obligated to remain on Grey's Anatomy despite a dispute over her salary, ABC Television says in a statement released Wednesday. "Katherine is an integral part of Grey's Anatomy and its success. Fortunately, we have a longterm contract to ensure she?ll be with the show for several years to come," says the statement. "In recognition of her tremendous talent and value to the show, we recently approached Katherine with an offer to raise her compensation significantly above the terms of her current contract. We were surprised to see this gesture reported negatively in the press, and want to reassure fans that she will continue as Izzie Stevens." On Tuesday, Heigl dropped out of contract talks with the show over salary, a well-placed source told PEOPLE at the time. "Katie is disappointed and hurt that (producer) Touchstone doesn't value her as much as her other costars, especially Sandra Oh and Isaiah Washington," the source said Heigl plays Dr. Isobel "Izzie" Stevens on the ABC hit medical drama.