Britain's towns and cities including Bristol are in danger of becoming "bland, homogenous metropolises" by the year 2029, one of the world's leading experts warned yesterday.
Historic parts of the city could be overrun with "identikit" shopping centres, office towers and sprawling "analogous housing estates".
Medieval architecture and iconic landmarks, including those in Bristol and elsewhere in the South West, are at risk of being "ensnared" by cheap and tasteless architecture as uninspired, cost-cutting developers resort to "one-stop" solutions.
The nation could lose its "quintessential Britishness" and begin to resemble the emerging cities of China and India within just 15 years unless urgent steps are taken to avoid the "collision course with mediocrity", the renowned placemaker David Twohig claims.
Twohig, the head of design at the Battersea Power Station Development Company, one of the most high-profile urban regeneration projects of the century, makes the daunting predictions in his new book Living in Wonderland: Urban Development and Placemaking, which hits the shelves this week.
He argues that the "clone crisis" has the potential of affecting people's health, wellbeing and general happiness.
The global phenomena could also harm foreign investment and economic success by "subduing a city's unique identity", Twohig claims.
"Over the next 15 years China is set to urbanise 300 million people and build the equivalent urban area of North America," he said yesterday.
"London alone is set to grow by two million people by 2030. This is the greatest period of urbanisation in human history and yet the buildings and places we are designing and developing leave a great deal to be desired."
According to the World Health Organisation, the world's population is set to rise to 6.4 billion by 2050. This will create unprecedented demand for housing in the UK and internationally.
Twohig warns that such high levels of urban growth may encourage designers and developers to opt for cheaper "lowest-common-denominator solutions".
Housing, offices and shops "from Dubai to Shanghai to London" are already "becoming identical". At the current rate of growth, "soulless architecture" will transform the look and feel of Britain's cities by the end of the late 2020s.
"The prospect of hundreds of millions of people ending up in nondescript developments without a sense of identity will lead to future social problems: alienation, isolation, crime and more," Twohig warns.
"It will also have economic repercussions. Local businesses are vital for injecting money into a community and attracting visitors, while bland developments will rapidly depreciate in resale value and discourage future investment.
"We are all moving in the direction of a default life; a sort of Zara-wearing model, living in a glass tower, eating whole foods, drinking in Starbucks and watching our local version of the X-Factor."