Under the 2003 deal, the combined dynamisation factor for GP pensions from 2003/4 to 2005/6 is expected to be about 48 per cent.
But health minister Lord Warner last week wrote to the GPC proposing to spread the dynamisation over five years to 2007/8 instead of three years.
GP leaders have rejected the plan and demanded that the DoH stick to its original promise. But the GPC believes the DoH could seek to impose its solution by the end of November, and has sought legal advice.
BMA pensions committee chairman Dr Andrew Dearden said that changing the contract retrospectively would breach contract law.
GPC chairman Dr Hamish Meldrum said: ‘There are suggestions the DoH can’t afford the original deal and doesn’t feel obliged to honour it.’
The five-year offer followed a proposal in August to cut dynamisation over the three-year period to 36 per cent, which was also rejected by the GPC.
A DoH spokesman said Lord Warner’s deal was ‘excellent’. He said: ‘Bigger increases than these can only be paid for by higher contributions from NHS employers, directly removing resources from patient care, and by higher contributions for all NHS pension scheme members.’
GPC member Dr John Canning said that it was particularly unfair to GPs who had postponed retirement to benefit from the new contract.