Labor Party leader Bill Shorten, in a pre-delivery text of a speech due Saturday night, said he would offer Australians a vote on whether to become a republic if his center-left party won the next election scheduled for 2019.

Turnbull, who led Australia's Republican Movement before he entered Parliament, visited the 91-year-old queen in London earlier this month. At that time, the premier said he was a "very strong Elizabethan," and would wait until her reign ended.

Australia, like numerous other Commonwealth countries with British colonial origins, has a governor general, Sir Peter Cosgrove - a former Australian army chief of staff - as the Queen's current representative "down under."

Whitlam-Kerr crisis

In 1975, the issue of whether to drop the monarch as ceremonial head of state and become a republic, came to a head when the then-governor general, Sir John Kerr, sacked Shorten's Labor predecessor Gough Whitlam as prime minister.

Malcolm Fraser, the conservative opposition Liberal Party leader at the time, was appointed interim prime minister until winning an election stipulated by Kerr one month later.

Still controversial but unclear is whether Queen Elizabeth II knew that Kerr was going to dismiss Whitlam's government, and whether Kerr actually had the power to do so.

'Yes' likely, says Shorten 

Shorten, a former trade union leader, in his text released before adding the Republican Movement on Saturday night, local time, said Australians could "vote for a republic and still respect Queen Elizabeth."

"I believe the answer will probably be 'Yes,' but we will let the people decide," Shorten said, according to quotes by federal broadcasting's ABC News.

"Our head of state should be an Australian," Shorten said.

In 1999, a similar referendum defeated the republican call, 55 to 45 percent.

A diversion from pressing issues?

ABC quoted the current deputy prime minister, Barnaby Joyce, as saying the question "is not what's pressing at the moment."

Australia's public was instead currently preoccupied with living standard issues such as "I cannot afford my power bill," Joyce said.

Shorten said that if his proposed referendum led to a yes vote, a secondary ballot would be held to decide on what form of a republic Australia should become.

As priorities, Shorten has said he wants recognition of indigenous Australians in the vast continental nation's constitution and has floated the idea of extending the term of Parliament from the current three to four years.

Letters still secret 

A Whitlam biographer, historian Jenny Hocking, plans to press the Federal Court in Sydney on July 31 to order the release of secret 1975 to 1978 letters between Kerr and the queen held by the National Archives of Australia.

Last week, Hocking told The Associated Press that it amounted to "national humiliation that we have to be even considering asking the queen whether we can look at these key records in our own history."

Under a 1978 deal between the queen's Buckingham Palace and the governor general's office in Australia, those letters are supposed to remain secret until 2027.

Kerr died in 1991 still rejecting in his memoirs media speculation that the United States' Central Intelligence Agency (CIA) called for Whitlam's dismissal over fears his government would have closed a US facility at Pine Gap in Australia's outback.

ipj/rc (AP, dpa)