Speake, who is listed in Marketing Week’s inaugural Vision 100 for her capabilities with both new technology and traditional media brands, joined ITV in September 2013 to oversee the marketing of ITV to brands and agencies.
Prior to that Speake spent seven years at Google in several senior positions including latterly as its UK strategic marketing director, where she led the marketing of its advertising solutions and tools.
ITV has confirmed her departure but has no further details on who will replace her or its plans for her role in the future.
The CMO role at Clear Channel is new and will see Speake become a part of the management team at the outdoor advertising company. She will have responsibility for driving its marketing strategy across its product portfolio including mobile and digital.
She will report directly to CEO Andrew Morley.
A spokesperson told Marketing Week that the role reflects the importance of marketing in Clear Channel’s future. Speake will start the new role in March.