A spinoff of 7-Eleven would jeopardize the convenience store chain's future growth by cutting it off from its parent's strength in the food business, the chief executive of Seven & I Holdings has said.

The comments from Ryuichi Isaka come as he faces a call for his ouster from shareholder ValueAct Capital, the San Francisco-based investment firm that holds a 4.4% stake in the sprawling Japanese retail conglomerate.

ValueAct has long been critical of Seven & I's conglomerate structure, calling for a spinoff of the 7-Eleven chain or for a sale of the entire company, but Isaka said that would not be in the chain's best interests.