The bizarre outcome was among the unintended consequences of Tuesday afternoon's surprise announcement, which saw the Abbott government subjected to ridicule in Parliament, newspapers and talkback radio, and across social media.

Speaking at the National Press Club, Opposition Leader Bill Shorten asked if the country was in a time warp, noting that not even John Howard had revived the British titles in his almost 12 years as prime minister.

With the Prime Minister on the defensive in Parliament, Labor used the announcement to claim the government's priorities were wrong. Privately some ministers expressed incredulity that Mr Abbott had taken such an approach without recourse to the cabinet or party room.

David Morris, national director of the Australian Republican Movement, said Mr Abbott's announcement had reframed debate from the ''celebrity monarchy'' to pride in Australia's national institutions.

''Mr Abbott's words and actions have given us a big shot in the arm,'' Mr Morris said. ''We won't get a republic while Tony Abbott is Prime Minister but he may help us get there.''

Mr Morris said membership had been growing strongly since Mr Abbott swore allegiance to the Queen when he became Prime Minister, after dropping away over recent years. Financial membership remained in the thousands, rather than the tens of thousands at the peak of the republican debate in the late '90s.

''If we can sustain the current interest we'll be back and back in a big way,'' he said.

But David Flint, national convener of Australians for Constitutional Monarchy, said the announcement was another triumph for the monarchist movement after the birth of Prince George last year.

A ReachTEL poll of more than 2000 Australians for Fairfax Media in February, found only 39.4 per cent of the population supports a republic - the lowest level in 20 years. The poll found only 35.6 per cent of 18 to 35-year-olds support the republic.

Mr Abbott confirmed on Wednesday he did not take his decision to cabinet or the Liberal party room.

Liberal senator Sue Boyce, a republican, said she was disappointed Mr Abbott had not taken the decision to the party room.

''I just would have hoped that we could go on with what are clearly well-accepted Australian honours,'' she said. ''I know that knights and dames are in the Australian honours system but we stopped using it in 1986 and I think that was a good move.''

Senator Boyce said she was disappointed outgoing Governor-General Quentin Bryce had accepted a damehood, but acknowledged most of her colleagues supported the move or were not perturbed.