The Vale of Aylesbury PCT draft policy asserts that where contractors wish not to register a patient they will have to use the formal closed-lists procedure.
GPC negotiator Dr Stuart Drage said this resurrected an argument over practices with open-but-full lists that was won three years ago.
'Every practice has the right to not register patients and that's acceptable within the regulations,' he said.
However, the PCT wants to implement the guidance which is in line with proposals for 2007/8 in the primary care White Paper, stating that practices should operate an open or closed list.
The PCT would also have the ability not to commission additional or enhanced services from them, including existing services.
Clare Blakeway-Phillips, director of primary care and development at the PCT, said: 'There is no open-but-full list because there is no maximum list size.'
The PCT proposes that where practices are unable to cope with workload pressures after three months, they should formally close their lists unless the PCT allows an extension.