Prominent Australian racing identities Gai and Robbie Waterhouse will travel with Prime Minister Anthony Albanese to London to attend the Queen’s funeral.

Mr Albanese, Governor-General David Hurley, their partners and 10 everyday Australians will fly out to London for the state funeral later on Thursday.

Mr and Mrs Waterhouse will also travel on Mr Albanese’s flight after being invited by Buckingham Palace to the funeral but initially finding they were unable to get to London in time.

“They were having difficulty getting across. As you can understand, it’s a bit full at the moment,” Mr Albanese told ABC Radio on Thursday.

“Australians would be very accepting that Gai and Robbie Waterhouse [are attending], with the relationship they had training, of course, the queen’s horses and having audiences with the Queen at Royal Ascot.”

Australia is providing travel support to officials and heads of state from commonwealth nations in the Pacific Islands including Papua New Guinea, the Solomon Islands, Tuvalu and Samoa.

While in London, Mr Albanese is expected to view the Queen’s lying in state at Westminster Hall and sign the official book of condolences.

Alongside his counterparts from other commonwealth nations, Mr Albanese will also meet the King at Buckingham Palace.

Mr Albanese said he would pass on Australia’s condolences during his one-on-one meeting.

“We must remember this is the loss of his mum, not just the loss of a monarch,” Mr Albanese said.

“King Charles’s statement, his first statement that he made was was quite extraordinary and really, really acknowledged that loss so soon after losing his father, of course.”

A statement from Government House said the governor-general and Mrs Hurley had spoken by phone with the King on Wednesday night and expressed the condolences of Australians at the passing of the Queen.

“He expressed the well-wishes of the Australian people to the King and His Majesty reflected on his admiration and affection for the people of Australia,” it said.

While away, Mr Albanese will also meet new British PM Liz Truss and Canadian counterpart Justin Trudeau.

On Wednesday it was confirmed 40 Australian defence personnel would also attend the funeral, with a number marching in the procession.

The Queen held several defence titles, including colonel-in-chief of the Royal Australian Engineers, Royal Australian Infantry, Royal Australian Army Ordnance Corps and Royal Australian Army Nursing Corps.

Meanwhile, more than 21,000 Australians have signed an online condolence book on the Department of the Prime Minister and Cabinet website.

Physical books are also available to sign at Parliament House and Government House in Canberra as well as official residences in other states and territories.

When Mr Albanese returns to Australia next week, a day of mourning will mark the life and service of the late monarch.

A national memorial service in Canberra will be attended by all state and territory leaders.

-AAP