A leading republican says hardcore monarchists are a dying breed, but if a rally in Canberra is any guide, the push for an Australian head of state is a little lifeless too.

Republicans were almost outnumbered by journalists when they gathered at Parliament House on Friday to call for a fresh referendum on the question of severing ties with the monarchy.

Ten years ago Australians voted against a republic on November 6.

Nationally, the "Yes" vote was only 45 per cent. No state had a majority in favour.

On Friday, Real Republic's David Muir insisted moving to a republic remained unfinished business.

"Under the constitution the Queen of the United Kingdom remains at the head of our system of government," he told reporters.

"How can we really establish our national identity while this remains the case?"

Mr Muir denied the poor turnout at the rally - just 15 republicans attended - reflected a general apathy among the broader community.

He also labelled as "absurd" Opposition Leader Malcolm Turnbull's suggestion that the republic shouldn't be revisited until Queen Elizabeth's reign is over.

"There's actually a greater appetite now for a republic in Australia," Mr Muir said.

"We need to push this now. It's an absurdity to suggest we should wait for some family succession to occur before we become a republic."

Earlier, Australian Republican Movement (ARM) vice-chairman John Warhurst declared there was "enormous passion in the community" for a republic.

"There are very few hard core monarchists and they are dying off every day, so let's get on with it," he told ABC Television.

Prime Minister Kevin Rudd claims to be a "lifelong republican" but for now he's focused on the economy "and a whole range of other priorities".

A push for a republic might be considered if the government is re-elected, the PM said on Thursday.

But Mr Muir argues that's not good enough.

"We are disappointed in our prime minister," he said outside parliament.

"Our national leaders need to listen to the Australian people ... they want this back on the agenda."

A major reason for the 1999 referendum's defeat was the split in republican ranks, with many - particularly the Real Republicans, who favoured the direct election of a head of state - voting tactically with the monarchists.

But now they're united, according to ARM chair Michael Keating.

All republicans agree the best way forward is to float alternative models at a plebiscite, with the winning selection to be put to the people at a subsequent referendum.

"When the people have indicated what model they want, we as republicans will campaign for whatever model the people want (at a referendum)," Mr Keating said.

That view was echoed by Women for an Australian Republic convenor Sarah Brasch, who joined her colleagues in Canberra to call for a "bipartisan" approach to reinvigorate the debate.