The news came on the same day that Mr Ross stepped down from his advisory roles linked to the 2012 London Olympics, the Financial Times (FT) reports.
Boris Johnson, the city's mayor, said he had "reluctantly" accepted Mr Ross's resignations from two consultancy roles, as well as his post on the body that oversees the distribution of lottery money for the event, the publication stated.
Mr Ross has also stepped down from the chairmanship of National Express after failing to disclose his use of shares in the bus and rail operator against loans.
The FT said his future with two other companies where he performed similar transactions - storage specialist Big Yellow and marine safety equipment manufacturer Cosalt - remains unresolved.
Mr Ross co-founded Carphone Warehouse in 1989 with Charles Dunstone.