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Nine Entertainment Co chairman and former treasurer Peter Costello has resigned from his role and stepped down from the company's board.
Costello, who was appointed in 2016, will be succeed by current deputy chair Catherine West.
In an email to all staff on Sunday afternoon, CEO Mike Sneesby said the board wished to thank Costello for his contribution to Nine over more than a decade, including eight years as chairman.
"Mr Costello played a key role in Nine milestones such as its successful re-listing on the Australian Stock Exchange in 2013, securing the landmark News Media Bargaining Code and the transformative merger with Fairfax Media," Sneesby said.
Costello thanked the board for their support over the last decade and particularly during the events of the last few weeks.
"I wish the board, the employees and the Company well," he said.
"There are enormous challenges ahead but I believe Nine is the best placed Australian media company to weather them and prosper."
Costello was treasurer of the Commonwealth of Australia from March 1996 to December 2007, and was the longest serving treasurer in Australia's history.
Last week Costello denied assaulting a journalist who was asking him questions in Canberra Airport about Nine's handling of allegations following the departure of TV news boss Darren Wick.
More to come…
