The simple answer is "No".
There is no compulsory purchase scheme in place for 'speculative' private housing.
If the land owners, who profess to care for the countryside and the production of 'home' crops, declined the opportunity to sell their land there could not be any houses. It really is as simple as that.
Still, I guess a nice crop of houses would provide their bank accounts with enough money to purge their consciences.....
The Wiltshire Local Plan sould be published on 3rd July.
Formal consultation is likely to commence in September.