Winston Peters, the acting prime minister of New Zealand, has taken another swipe at Australia, accusing it of “copying” the New Zealand flag.

Relations between the Pacific neighbours have been growing noticeably frostier since Jacinda Ardern’s leave of absence, amid Australia’s continual deportation of New Zealand citizens. Experts say the increasing tensions are fundamentally altering the once robust and “special” relationship.

Peters – well-known for his blunt rhetoric – is now demanding that Australia change its flag because it is too similar. “We had a flag that we’ve had for a long time, copied by Australia, and they should actually change their flag and honour the fact that we got there first with this design, being decided by a prime minister and his legacy,” Peters told TVNZ.

A poll administered by the New Zealand Herald found 62% of respondents supported Peters’ call for Australia to change its flag.

This is not the first time Peters has called on Australia to come up with a new flag design, arguing in a 2016 opinion piece that New Zealand’s flag should be restored to its “unique” status.

“One argument used against our flag is that it is too like Australia’s, which borrowed our design in the first place,” Peters wrote. “However, since Australian political leaders have recently signed to have their own head of state it is Australia that will have to change its flag, and soon. That will rightly restore our flag to being unique as it was in the beginning.”

The New Zealand and Australian flags bear a striking resemblance, with both featuring a royal blue background, a union jack in the lefthand corner, and the southern cross.

The New Zealand flag is 50 years older than Australia’s and was adopted in 1902, replacing the union jack. The Australian flag was adopted in 1954, after going through three previous iterations since 1901.

New Zealander William Stevens was one of five winners who submitted a design for the Australian flag in 1901, all of which were so similar they were described as identical at the time, with commentators joking that if New Zealand decided to become part of Australia changing the flag would be a simple process with another star added to the southern cross.

Both the Australian and New Zealand flags are based on the British blue ensign.

Two years ago, New Zealand’s government spent NZ$26m holding a referendum on changing the New Zealand flag. In the end, 56.6% of New Zealanders voted to stick with the status quo, while 43.2% opted for a new design by Kyle Lockwood that featured a silver fern.

The current New Zealand flag flutters next to the alternative suggestion during the 2016 referendum.



Photograph: Marty Melville/AFP/Getty Images

Bill English, the deputy prime minister at the time, said there had been a “robust democratic process” that allowed New Zealanders “to discuss who we are and how we want to be represented on the world stage”.

The two flags have sometimes been mixed up on public occasions. Earlier this year the nine network used a graphic of the New Zealand flag during Australia Day coverage, while the Australian and New Zealand flags were mistakenly switched during a medal presentation at the Rio olympics.