Ed Richards, chief executive of telecoms regulator Ofcom, is to relinquish his post and step down at the end of the year.
He will continue to handle all operational, financial, economic, competition and policy matters until the end of December.
Richards previously served as senior policy advisor to prime minister Tony Blair for media, telecoms, the internet and e-government, and controller of corporate strategy at the BBC.
Along with former culture secretary Tessa Jowell, he was a key influence on the Communications Act 2003, which established Ofcom.
The act also outlawed piggybacking – accessing the internet without intent to pay – and malicious communications on social media.
Richards joined Ofcom as a board member shortly after its establishment. He was promoted to chief operating officer in 2005 and chief executive a year later, succeeding Digital Britain report author Stephen Carter – who became minister of communications, technology and broadcasting, and later joined Alcatel-Lucent.
Patricia Hodgson, Ofcom chairman, said: "Ed has been an outstanding chief executive. Under his leadership, Ofcom has helped deliver superfast broadband, 4G, lower prices, innovation, competition, and sustainable public service broadcasting in the UK.
"He leaves an impressive legacy. On behalf of the board I would like to thank him for his enormous contribution."
Richards said: "It has been a privilege to lead Ofcom during such an exciting and dynamic period in the evolution of the UK's communications sector.
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"It is never easy leaving a job that you enjoy greatly but I have always felt that, once I had completed eight years as chief executive, this would be the right time to move on."
The post of chief executive at Ofcom is a public appointment made by the regulator’s board, involving an independent assessor.
The search for a replacement is understood to already be underway, with the appointment expected to be announced early in 2015, said Ofcom.
The appointment of Richard’s successor will be subject to approval by the secretary of state for culture, media and sport, Sajid Javid.