MELBOURNE—Rio Tinto media relations advisor David Luff has taken on global media relations responsibility at the mining giant, after the departure earlier this year of Christina Mills.

Mills, who was based in London, left Rio Tinto after seven years as global head of media relations, during which she helped navigate the British-Australian mining giant through a variety of sensitive issues.

According to a Rio Tinto spokesperson, her duties have since been assumed by Luff, who becomes global practice leader for media relations, after previously holding the role of chief media relations advisor to Rio Tinto in Australia.

The move is part of a restructuring at Rio Tinto, which followed the departure of Mills in August. Media relations has since been merged with corporate communications, under the oversight of global practice lead Simone Niven, who previously led internal comms, digital media and branding. Luff reports to Niven.

A former journalist at Sydney's Daily Telegraph, Luff rose to prominence during his tenure as senior media advisor to Australian Prime Minister John Howard, where he was dubbed the "secret weapon" during the 2007 election campaign.

Following a four-year stint in politics, Luff moved to Telstra before joining Rio Tinto in 2009.