Kroger said on Monday Chief Executive Officer Rodney McMullen has resigned from the post after a board investigation found that his personal conduct was inconsistent with the grocer's "policy on business ethics".

His departure follows a company board investigation into his conduct “unrelated to the business,” the grocer said.

Longtime Kroger CEO Rodney McMullen has resigned after an internal investigation found that his personal conduct was "inconsistent" with the company's ethics policy.

Kroger on Monday said its longtime chief executive Rodney McMullen has stepped down after a probe into his personal conduct revealed inconsistencies with the grocery chain’s ethics policy. The company said it was made aware of “certain personal conduct” by McMullen on Feb.

Chris Brigati, chief investment officer and managing director of SWBC, said the sudden resignation of Kroger CEO Rodney McMullen for an ethics violation should force the grocery chain to put more checks in place so that there is "nothing further throughout the company that can be disruptive.

Cincinnati-based grocer Kroger announced on Monday the abrupt resignation of its CEO Rodney McMullen, citing "personal conduct" that was inconsistent with company policy as the reason for his ousting.

The conduct is not related to financial performance, operations or reporting, and it did not involve any Kroger associates, the company said.