Media speculation that Senator David Johnston could be replaced as Defence Minister had grown since he told the Senate he wouldn’t trust government-owned shipbuilder ASC “to build a canoe”.

Adelaide-based ASC is building three Air Warfare Destroyers for the RAN, a project that is running late and at least $350 million over budget.

“I’m being conservative, it’s probably more than $600 million, but because the data is bad, I can’t tell you,” Johnston told the Senate on November 25. The canoe comments sparked widespread criticism, especially from the SA state government and unions representing ASC staff, and saw the Minister censured by the Senate. Johnston subsequently backtracked from the comments, calling them a “rhetorical flourish”.

Appointed Shadow Minister for Defence in 2008 and Minister with the election of the Abbott government in September 2013, Johnston said in a statement that: “It had been a great privilege to serve in this role”.

Said Prime Minister Tony Abbott in the statement announcing ministerial changes: “I record my gratitude to Senator the Hon David Johnston who will stand down as Minister for Defence. Senator Johnston has done a fine job in restoring investment in the Australian Defence Force after six years of neglect and has effectively managed the deployment of Australian Defence Force personnel to Europe and Iraq.”