Ministers have pledged that from this month every patient in England should be offered a choice of at least four hospitals but GPs are not contractually bound to provide this.
The DoH is relying on the new directed enhanced service (DES), due to be implemented from April, to encourage GP involvement in the scheme, which has been dogged with software and information problems since its introduction.
GPC negotiator Dr Richard Vautrey felt that money invested through the DES would be an incentive but perhaps not enough for all practices.
'The DES is only a minimum level of funding. We're happy for local agreements that go over these arrangements,' he said.
Dr Vautrey said that the GPC was aware of a number of areas where PCTs had employed 'vigorous' tactics to involve all GPs, and stressed that GPs must not let themselves be bullied into taking part.
Dr Gillian Braunold, joint clinical lead at Connecting for Health, was more optimistic.
'Often GPs may say "never". The minute you send money for Choose and Book never becomes a maybe,' she said.
However, Watford GP Dr David Lewis said that he was 'not convinced at all by the new enhanced service'.
He said that a rough estimate of income before tax of nearly £1,500 for his practice represented 'meagre compensation for the three partners who must devote additional time and effort to assist staff to implement Choose and Book for our patients, while there is a lack of evidence of the clinical benefit'.
'The time it takes for extra consultations could be as much as 25 hours a week. You simply can't fund that,' he said.
'Although there's no contractual obligation we will do what we can with resources available.'
A DoH spokesman said that '100 per cent of PCTs have reported that they have plans in place to offer choice from January 2006'.