Monarchists in Australia have accused the state premiers of "insulting" King Charles as they will not be present at a reception welcoming him to the country.

The King's visit, which begins later this week, will include a reception in Canberra, but the six state premiers - of New South Wales, Victoria, Queensland, Western Australia, South Australia and Tasmania - have said they're unable to attend.

"I find it insulting," said Bev McArthur of the Australian Monarchist League. "They should just take off their republican hats, make the short trip to Canberra, say 'hi and thank for you coming to Australia'."

Buckingham Palace is not commenting on the row - but the Australian states will all have representatives at the event, including their governors.

The King will also be formally welcomed by the country's Prime Minister, Anthony Albanese.

It is a visit which has re-opened questions about whether Australia should become a republic - with this so-called "snub" at the reception being highlighted by the Daily Mirror.

Bev McArthur, a pro-monarchist campaigner and Liberal MP, told ABC News radio it was an "insult" that state premiers were not going to the reception next Monday.

"The failure of state premiers to attend the reception in Canberra is completely indefensible," she told the BBC, accusing them of "gesture-led politics".

"Welcoming the King and Queen to Australia is the least they can do as the most senior elected representatives of their states," she said.

Writing on social media, she said the King was being "snubbed".

Mrs McArthur was unconvinced by the excuses from the regional heads of government - which included having other commitments and meetings that day - telling the BBC it was "petty and inhospitable".

The premier of Victoria, Jacinta Allan, cannot go as she's tied up with other government business, but in a recent press conference said she was "very pleased that King Charles is visiting Australia".

Asked about her view on Australia becoming a republic, she said it was “something I would support but it is not something that is a top priority for me right now”.

The premier's deputy will not be going either, so the state will be represented by Victoria's governor, Prof Margaret Gardner.

Mrs McArthur, speaking on behalf of the Australian Monarchist League, said that constitutional monarchy offered a "very stable system of government" and that an elected president would mean another layer of government.

She said that the latest polling in Australia showed more people still wanted to be a constitutional monarchy than a republic.

But the Australian Republic Movement is calling for an end to the King's role as Australia's head of state - and has called the royal visit the monarchy's "farewell tour".

"It’s time for Australia to elect a local to serve as our head of state. Someone who can work for Australia full time," said spokesman Isaac Jeffrey.

In an exchange of letters with the Australian Republic Movement, the King has confirmed that whether Australia becomes a republic is a "matter for the Australian public to decide".

The visit to Australia will be the King's biggest trip since his cancer diagnosis earlier this year.

His treatment is expected to be paused during the trip.

After the Australian leg of the trip, the King and Queen will travel to Samoa for the Commonwealth heads of government meeting.