The designer behind the man next in line for the British throne has launched an attack on the country’s architects, who he says are being “infantile” in pursuing ego-driven visions and creating “disappointing to dismal” design.

One of Prince Charles’ allies in his battle against modern architecture, Andres Duany, has riled Britain’s architects by unveiling a 64-point litany of mistakes they’ve made over the past 50 years.

Duany, one of the original designers of the Prince’s new town in Dorset, Poundbury, said some of the leaders of modern architecture, including Richard Rogers, Frank Gehry, Zaha Hadid and Peter Eisenman were “increasingly irrelevant”, The Guardian reported.

But describing the barrage of abuse as a case of “pot calling the kettle black”, Bates Smart Melbourne-based architect Kristen Whittle told Architecture & Design it is Prince Charles who has “had quite a negative effect on architecture in the country”.

The prince does not represent a balance point of view, Whittle argued. He “harks back to some semi-medieval classical approach to architecture where village life and the monarchy were represented in either small, local, tiny villages with a big castle or a country mansion”, he said.

“That sort of approach to country towns is where he is coming from. But that’s not the modern era.” Leading modern architects, the prince and his allies are regularly embroiled in theoretical disputes about architecture. One British architect, president of the Royal Institute of British Architects Sunand Prasad, recently claimed Duany was “living in another world”.

While acknowledging architects’ craft skills and traditional knowledge had often been sidelined between the 50 and 70s, he said architects were now building the “highest performance” buildings ever.

Whittle argued Prince Charles’ aversion to modern architecture does not represent the growth of industry, urbanism or modern life. “Architecture needs to represent its situation and its era. Why should we hark back to the medieval era? It seems a bit farcical to me,” he said.

Whittle, who came from England three years ago to live in Australia, said there are two streams of consciousness in England — the metropolitan attitude of people living in cities, “and the more conservative attitude of the countryside where everything looks like 17th Century England”.

“If you live in that space you see modern England as a bit brutal. But people in the cities have lives that are commensurate with what is going on in the world, and are enlivened by it.”

In his list of “disappointing and dismal” architecture, Duany cited “gratuitous shapes” in buildings such as winged roofs that quickly go out of fashion, as well as “amazingly rude” colours on shop signs and civic buildings that “look common” when they should be grand.