Minister at Singapore defence summit also reveals Australia to buy only second-hand Aukus submarines from US Get our breaking news email , free app or daily news podcast Minister at Singapore defence summit also reveals Australia to buy only second-hand Aukus submarines from US Get our breaking news email , free app or daily news podcast The defence minister, Richard Marles , has said the “seabed is a battlefield” in a combative speech urging Beijing to be more transparent about its maritime