Veteran broadcaster Sir Michael Parkinson says it is only a matter of time before Australia became a republic. Parkinson was speaking to reporters in Sydney after becoming the first foreigner to deliver the annual Australia Day address in its 15-year history.

''Why should Australia not be a republic? It's its own country, its own man,'' he said, adding the period after Queen Elizabeth either dies or abdicates would be an ''acceptable'' time for the nation to formally sever ties with the British royal family.

Prince William is the latest member of the British royal family to visit Australia, completing a tour in 2010.

"My own guess would be that whenever anything happens to the present queen, that would be the time when Australia, with great delicacy ... will do it.

"I think that would be acceptable and understood by everybody," Parkinson said.

Australia last held a referendum on the issue in 1999, with proposals for presidential rule defeated.

The current prime minister - Welsh-born Julia Gillard, who moved to the continent when she was five - has previously said Australia should consider the issue of republicanism at the next change of monarch.

Englishman Sir Michael Parkinson was chosen to give a foreigner's view of Australia, after being a regular visitor to the country for more than 30 years. The Australia Day speech is usually given by a well-known Australian public figure, academic or writer, making Parkinson a controversial choice.

When the decision was first announced, comments on the official website were largely angry that a Brit had been chosen.