Greens Leader Richard Di Natale is marking the Queen's Birthday by setting out a 5-step path to allowing Australians to serve as our own heads of state.

"We are a mature, independent, confident nation and it's time to stand on our own two feet " Senator Di Natale said.

"It's on days like today that many Australians remember the failed republic referendum of 1999. The Greens have a clear plan to ensure history doesn't repeat itself.

Greens Leader Richard Di Natale says it's time for Prime Minister Turnbull to articulate a timetable for Australia becoming a republic.

"There's never been a better time for Australia to become a republic," Senator Di Natale said.

"For the first time, all three federal political leaders are in favour of a republic, and with the state and territory leaders declaring their support, there's huge momentum.

"Malcolm Turnbull was the head of the Australian Republican Movement, so it's time for him to show leadership on the issue now that he's Prime Minister.

The Australian Greens are joining the community in welcoming the Duke and Duchess of Cambridge and baby Prince George of Cambridge to Australia, but say today is an occasion to consider why we wouldn't welcome them as friends from another country, rather than as future heads of state for Australia.

I hope you are all having a pleasant and inspiring evening. My apologies for not being able to be with you in person but I thank David for the opportunity to have this short message read to you all.