Ryan Graves, senior vice president of global operations at Uber Technologies Inc., is stepping down from his operating role in September, Graves wrote in an email posted by CNBC.com on Aug. 10.

Graves, who was Uber's first full-time CEO and employee, will remain a board member of the ride-hailing company, as per his email that he sent to company employees. The company is currently looking for a new CEO after Travis Kalanick resigned as chief executive after demands from Uber's investor that he step down following a sexual harassment probe.

Garrett Camp, co-founder and director, recently informed employees that Kalanick is not returning to the company to resume his CEO role.