PETERSFIELD town councillor Jamie Matthews has told a meeting that will decide if 200 houses should be built in the town that the proposal fails to meet policies set out in the Petersfield Neighbourhood Plan (PNP).
The PNP says fields on Causeway Farm in Petersfield are suitable for for a 200 home estate, and sets out conditions such a development should meet.
Cllr Matthews, who was on the neighbourhood plan steering committee, said: "This proposal fails to meet a number of conditions laid out in the PNP, quality, drainage, infrastructure, are just three.
"This is the largest and most sensitive development proposed in the PNP and is therefore a key test of the PNP.
"If it is approved without meeting PNP conditions then a precedent will be set that will allow PNP conditions to be ignored by developers in the future."
The Petersfield Society and the Campaign for the Protection of Rural England also said the proposal from David Wilson Homes, Bovis Homes and 4L is refused.
The South Downs National Park Authority planning meeting in the South Downs Centre in Midhurst is expected to last until at least lunchtime today.