Atkinson moved to Australia on 1 November to take up the role of interim chief executive while a permanent chief executive was appointed, following the departure of former Adshel chief executive Steve McCarthy.
Before being promoted to chief operating officer in June 2011, Atkinson was managing director of Clear Channel Outdoor UK. He was acting chief executive between Barry Sayer's departure in 2009, and the arrival of Matthew Dearden in 2010.
After joining Clear Channel as sales director in April 2005, Atkinson became group sales director in May 2005, and then managing director in 2008.
A well-known figure in the media industry, Atkinson previously held various senior roles at Associated Newspapers, including commercial director of the newspaper, Ireland on Sunday, and head of trading, newspapers, at The Mail on Sunday
Atkinson said: "I love the UK media industry, and in particular Clear Channel. I'm very proud of all we've done to build the Clear Channel business, and the great partnership that Matthew and I built working together.
"So it's taken a very special opportunity to tempt me away. I am energised by the great potential of Adshel Australia and New Zealand, and will enjoy working with our great people here to deliver outstanding results."
Adshel was formed in 1997 as a joint venture between APN News and Media, and Clear Channel, and claims to have the largest street furniture coverage in Australia, with more than 14,700 illuminated ad panels.
Dearden said: "Rob is an immensely talented and likeable man who we will miss. This is a great professional and personal opportunity for Rob and his family.
"Rob is perfectly placed to lead the Australian and New Zealand markets at this exciting time, having spent the last five months there. We wish him and his family all the best for their new adventure.
Dearden is expected to announce his plans for the future structure of the UK business later today (21 March).
Clear Channel called in consultants McKinsey & Company to work on a restructure of its commercial team last year, prior to the departure of former sales director Steve Atkinson.
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