King Charles and Queen Camilla have locked in plans to visit Australia and Samoa in October but have called off a proposed trip to New Zealand on health advice as the king recovers from a cancer diagnosis.

The Australian government said on Monday that the king and queen would travel to the Australian Capital Territory and New South Wales during the visit, with further details to be confirmed later.

The announcement coincided with the release of official Australian portraits of the king and queen.

All Australians are eligible to request a printed portrait of the monarch courtesy of their federal MP or senator, as part of the little-known nationhood material program, but the federal government had been waiting for Buckingham Palace to send an official portrait.

“In the official portraits, The King wears The Sovereign’s Badge of the Order of Australia, while The Queen wears the Wattle Brooch which was gifted to Her late Majesty Queen Elizabeth II during her visit to Australia in 1954,” the Australian government said in a statement.

Buckingham Palace said Charles and Camilla would attend the commonwealth heads of government meeting (Chogm) in Samoa, which is scheduled for 21-25 October.

They will visit Australia but not New Zealand as Charles, 75, continues his recovery from cancer after he was diagnosed earlier this year. The king returned to public duties in late April.

“The king’s doctors have advised that such an extended programme should be avoided at this time, to prioritise his majesty’s continued recovery,” a spokesperson for Buckingham Palace said.

The Australian prime minister said he would be “honoured to welcome the king and queen on their first royal visit to Australia later this year”.

“They are always welcome visitors,” Anthony Albanese said on Monday.

“The king has a deep regard for our great nation, and has always spoken warmly of the time he has spent here and the astounding beauty of our extraordinary continent.”

Australia’s governor general, Sam Mostyn, said she looked forward to “showcasing the very best of our modern and diverse nation” during the royal visit.

“I was fortunate to spend time with his majesty in May,” she said.

“His majesty the king has a well-known deep affection for and connection to the people of Australia and he was very much looking forward to his first visit to Australia since becoming king.”

It will be the first visit to Australia by a reigning monarch since 2011, when Queen Elizabeth II and her husband, Prince Philip, made a 10-day tour of the country.

The Australian Republic Movement said the visit was “a great opportunity for all Australians to ask themselves whether the British royals really represent a modern Aussie democracy”.

The ARM’s national director and chief executive, Isaac Jeffrey, said the organisation welcomed the visit but questioned the cost to Australian taxpayers.

“While we respect the role the royals have played in the nation to date, it’s time for Australia to elect a local to serve as our head of state: someone who can work for Australia full time and advocate for Australian industry, charities, economy, trade, jobs and people – like Charles does for the UK,” he said.

Jeffrey said his organisation had asked for a meeting with the king during the visit. He said this was “not to ask his permission to become a republic, because only the Australian people can make that decision”.

“We’ve asked to meet so we can let him know Australia and the UK will continue our strong alliance, friendship and sporting rivalries when we become a republic. We’re keen to tell him we’ll stay in the commonwealth and a republic is about us, not about him or his family.”

There is no sign the government is preparing to put the question of a republic to the people in a referendum. The idea was last defeated in a 1999 referendum.

The assistant minister for the republic, Matt Thistlethwaite, told Guardian Australia last year that the defeat of the Indigenous voice referendum made a republic “a lot harder” although Labor “remains committed” to the idea.

Additional reporting by Reuters