Conservative hero and Australia's second longest-serving Prime Minister John Howard not only "trembled" at the thought of a Trump Administration but admitted he would have struggled to vote for one.

But in a wide-ranging interview on Thursday, Mr Howard presented a more sanguine view of Mr Trump in office, a man he said Australians could trust as an alliance partner, expected to last a full term and who was being condemned too hastily as a scandal involving Russian connections with his campaign ensnares family members.

"People who are writing him off now are foolish – a lot of people doing that still can't accept that they lost [the election]," Mr Howard said. "You've got to look through the style. The things that disconcert people about him are more on the style side."

Speaking at the Museum of Contemporary of Art at an event by the United States Studies Centre at The University of Sydney, Mr Howard said it was too early to say if Mr Trump would be a success.