The Australian government came under mounting pressure on Australia's national day on Tuesday to appoint an Australian head of state to replace the British monarch.

Every Australia Day, an eminent Australian citizen is made Australian of the Year in recognition of his or her contribution to Australian society.

The 2016 Australian of the Year, former Chief of Army David Morrison, said in his acceptance speech on Monday night that he intended to use his new public profile to campaign for Australia severing its constitutional ties to Britain.

Britain's Queen Elizabeth II is also Queen of Australia. A referendum that would have replaced her with an Australian head of state was soundly defeated in 1999, with the then Prime Minister John Howard campaigning against change.

However, support for the so-called Australian Republic Movement, which advocates for an Australian head of state, is growing.

Morrison said it was time another referendum was held on who should be Australia's head of state.

"I am a member of the republican movement, I have been a republican all my life. When I was serving in the army, these views were very private," Morrison told Australian Broadcasting Corp. on Tuesday.

"Now, without giving it undue resonance, I do intend to at least contribute to a national debate, if we're going to have one, about where we might go in the future," he said.

This week, all but one of the leaders of Australia's eight states and territories signed a declaration of support for the Australian Republican Movement's quest to have a national vote on Australia becoming a republic by 2020.

On Australia Day last year, former conservative Prime Minister Tony Abbott, a staunch monarchist, created a furor by announcing that he had made the Queen's husband, Prince Philip, a knight. Many thought Abbott should have used the national day, which marks the arrival of the first British colonists in Sydney in 1788, to honor a worthy Australian.

Abbott was replaced in September by Prime Minister Malcolm Turnbull, who was chairman of the Australian Republican Movement at the time of the 1999 referendum.

But many in his government want the British monarch to remain Australia's head of state, and after becoming prime minister Turnbull said he was in no hurry to sever the nation's constitutional links to Britain and did not believe there should be another referendum until after the Queen's reign ends.

"Frankly, there was more momentum in the late 1990s than there is now," Turnbull told reporters Tuesday, referring to the public mood. "I've led the 'yes' case for a republic into a heroic defeat once, I've got no desire to do so again."

Opposition leader Bill Shorten said Australia should not delay in holding a referendum.