It's the cycle of life, even on the walls of the National Portrait Gallery.

When a dignitary dies, staff are always at the ready to retrieve the relevant portraits from the gallery's vast archive and find space on its walls to pay tribute.

But when two former prime ministers die just six months apart, a bit of judicious rearranging is in order.

Former liberal prime minister Malcolm Fraser, who died Friday morning, has now taken up residence on the wall that until then had been devoted to a tribute to his political nemesis Gough Whitlam, the Labor prime minister he infamously ousted and who died in October.

Space was made for a famous black-and-white photograph of Fraser at Randwick Racecourse, captured in 1975 by Roger Scott, and a 1981 painting by Bryan Westwood, showing a relaxed Fraser in a dove-grey suit leaning against a flowered armchair.

The tribute wall is now in the unusual position of honouring two former leaders who, in their working life, were arch enemies.

Later in life, the two men reached a rapprochement when it came to personal politics.

Perhaps the tribute wall should become a permanent feature of the National Portrait Gallery's displays.