A local council is being taken to court over plans to build a four-bedroom house on a protected stretch of coastline.
Approval for the two-storey house at the "spectacular" Rame Head Area of Outstanding Natural Beauty (AONB) was a "terrible mistake," objectors claim.
Cornwall councillors voted to approve it despite the authority's planning officer recommending refusal.
Applicant Chris Wilton said criticism had been "ridiculous" and "misleading".
Rame Protection Group has been granted a judicial review into the decision but no date has yet been set.
Farmer Mr Wilton, who is the chairman of Rame Parish Council, was given rights to build an "agricultural worker's dwelling" with four bedrooms and farm office, balcony, garden, double garage and parking in August, under an agricultural tie.
Malcolm Cross, from Rame Protection Group, claimed the property would be worth £1m with its sea views and said: "Rame Head itself is a spectacular setting... It's always regarded here as tranquil, calm, very unspoilt. This will lead to more development.
"We think it's the thin end of the wedge and will set the wrong example for Cornwall".
Cornwall Area of Outstanding Natural Beauty Unit objected to the plans as the house would "form a prominent new skyline landmark" and would "offer an unwelcome assertive presence".
Mr Wilton said the "£1m" price tag was not correct and claimed a false impression had been given by objectors that he would be building a luxury home in the middle of the Rame Head cliff top.
He told the BBC he would be living in the new house, adjacent to existing cottages, and that it "sets no precedent at all" for further building to be allowed in the area.
He said some of the comments being made were "just ridiculous" and that "each application is taken on its individual merits".
Cornwall Council said the decision to grant planning permission would be "robustly defended" during the review.