Plans for a 20,000-house development in rural Leicestershire could go ahead without proper local consultation, officials have warned.
The eco-town would be located on the edge of Leicester
The Co-op wants to build the eco-town near Leicester but locals believe it would overwhelm existing services.
Some fear it may get direct government planning approval under a national scheme and thus bypass local scrutiny.
But the Co-op said it was holding a private briefing this week for concerned councillors and MPs.
The government wants to build 10 carbon-neutral, self-contained soc-alled eco-towns around the country.
The Co-op and English Partnerships are bidding to create about 20,000 homes along with services on land between Houghton on the Hill, Oadby and Great Glen.
Harborough council leader Graham Hart said: "Normally they come into the district council and our officers deal with it and we as local politicians are brought into the loop and the public are.
"This one is going to central government and coming down to us - it could be as a fait accompli."