It has been a long time since anyone has said anything nice about Scott Morrison, so it was little wonder the former prime minister looked slightly bemused on Thursday as friend and foe alike sang his praises.

Upon the leaking of the details of the submarine arrangements that will underpin AUKUS, and which will be announced on Tuesday, acting Prime Minister and Defence Minister Richard Marles paid tribute to both Morrison and his former defence minster, Peter Dutton, the architects of the tripartite security pact.