With the green belt around Cambridge facing mounting pressure from housing developers and the Government Liberal Democrats are alarmed by the head of Natural England suggesting it should be replaced by "green gaps".
Dr Helen Phillips, chief executive of Natural England the body in charge of protecting the natural environment, has said that "rather than surrounding cities with no-go areas for new housing, it was time to find better uses for green belt land."
Her controversial comments came as Natural England published its first State of the Natural Environment Report - a look at how landscape and wildlife are changing.
Dr Phillips said Natural England was not in favour of urban sprawl but said much of the green belt was neglected and poor quality.
She said: "rather than a blanket ban on building, planners should find ways of creating green gaps, wedges and corridors that helped wildlife and made better use of green spaces next to cities."
Jonathan Chatfield the Lib Dem parliamentary spokesperson for South East Cambridgeshire said:
"There is great concern in the villages surrounding Cambridge that urban sprawl will eventually engulf them in one big greater Cambridge. The green belt is the one thing stopping that from happening.
"Natural England is a semi governmental organisation formed by the amalgamation of the Countryside Agency and English Nature and as a statutory consultee it has enormous clout in planning matters.
"This smacks of the Labour government getting a quango which should be protecting our rural environment to do its dirty work to push through its unpopular new build housing policy."
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