Australian Prime Minister Scott Morrison announced a new Cabinet member on Saturday after a wave of high-profile ministerial resignations added to opinion polls that suggest the center-right government faces heavy defeat at elections due in May.

Morrison will need to retain all the parliamentary seats held by his coalition government, but his chances are at risk from a wave of incumbent lawmakers in marginal seats set to retire.

Australia's Defence Minister Christopher Pyne and Defence Industry Minister Steven Ciobo both announced on Saturday morning that they would not stand in elections due in May.