Prime Minister Anthony Albanese will reaffirm the strong relationship between Australia and the UK when he meets with King Charles III ahead of the Queen's funeral.
Mr Albanese will touch down in London on Friday night before he has an audience with the new head of state on Saturday.
"No doubt we'll also talk about the relationship with Australia - he (the King) has a strong relationship," Mr Albanese told 6PR radio before leaving Sydney.
"He finished his high schooling in Victoria and has had many visits here to Australia.
"We both are very strong democracies ... we have very similar traditions and it will be important to strengthen the relationship in the future."
The prime minister is leading an Australian delegation to attend a number of official events before the Queen's state funeral, to be broadcast live at 8pm AEST on Monday.
The travelling party includes a small group of "everyday Australians".
A separate aircraft is transporting officials from Pacific island countries.
Opposition Leader Peter Dutton said the outpouring of emotion for the Queen was obvious and it was great the Australian delegation was able to represent the country.
Thousands of people have joined a kilometres-long line stretching across London to pay respects as Queen Elizabeth II lies in state at Westminster Hall.
Australian traveller Tiffany Wertheimer spent more than seven hours in a queue to say farewell to the late monarch.
"I arrived at the back of the queue which was a really weird feeling, obviously many more people joined immediately, but for that split second I was at the back of an enormous queue that runs through central London," she told 2GB radio.
"I've had a few moments when I was going to call it quits."
Debate about the future of the monarchy in Australia continued despite Mr Albanese insisting it was not the right time to address the matter.
Former prime minister Julia Gillard said it was natural for Australians to reflect on any wider significance following the symbolic end of an era with the Queen's death.
"I've always thought inevitably when the reign of Queen Elizabeth came to the end that people would reflect, but people will do that in a very measured and unhurried way," she told BBC radio.
Ms Gillard, a self-described lifelong republican, said Australians could expect a discussion on constitutional change in the coming years but agreed now was not the time.
While in London, the prime minister will meet with British Prime Minister Liz Truss and his Canadian counterpart Justin Trudeau.
Mr Albanese is expected to view the Queen's lying in state at Westminster Hall and sign the official book of condolence.
A day of mourning will be held in Australia on September 22, after Mr Albanese returns, with a public holiday to mark the occasion.
Parliament will also meet on September 23 to allow the prime minister, opposition leader, MPs and senators to speak on a condolence motion.
