A proposed new city that one million people could one day call home has been branded a "dangerous idea" that the government should "kill off".
Shiv Malik and Joseph Reeve want to develop their Forest City on 45,000 acres of land east of Cambridge, and between Newmarket and Haverhill in Suffolk.
The entrepreneurs believe it could "solve Britain's housing problems" and are seeking planning powers from Westminster to help deliver the project.
But in a letter sent to Labour Housing Minister Angela Rayner on Wednesday, Conservative MP for West Suffolk, Nick Timothy, urged government to "rule it out".
"The developers look at the people of West Suffolk with contempt," he said.
"I hope you will take a different approach, respect the principle of local consent, and kill off this dangerous idea for good."
Timothy pointed out its size and population density would be similar to that of a large and densely populated city.
"This is before we consider the physical realities of building a sprawling metropolis in a region where supplies of drinking water are already under stress."
Malik, of Albion City Development Corporation, said the city would have 400,000 affordable homes, boast 8,000 acres of commercial space and a 1,600-acre lake.
He said the project was "absolutely not" a dangerous idea.
"He doesn't understand just how much value can be generated, not just for the city, and therefore the citizens of the city, but also for the wider region," he said.
Last month, the then Housing Minister Matthew Pennycook said the project was "speculative" and failed to qualify for Labour's New Towns programme.
The government could still, however, agree to the creation of an independent body and grant it "compulsory purchase and planning powers" to deliver the city.
This is how Canary Wharf and the 2012 Olympic site were delivered in east London.
Timothy started a petition opposed to Forest City, and says many of his constituents are against it.
But Malik said it could "save the whole of Suffolk from urban sprawl that everyone hates".
"Any change, any development, always comes with worries and concerns and I think this stems from a huge lack of trust around change, and rightly so," he said.
"For 20 years, people have seen development without the requisite infrastructure – and it's often ugly and incredibly unaffordable, so they're right to distrust anything.
"So, it is a big ask, but what we're asking people is to now trust us."
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