The GPC has called for an increase in net income of 4 per cent this year, which would mean more than 40 per cent of practices no longer need MPIG.
Those still on MPIG would get a 1.1 per cent core pay rise, while practices that have never had MPIG would receive in excess of 8 per cent under the funding deal agreed in October.
In evidence to the Doctors' and Dentists' Review Body (DDRB), the GPC called for a 3.5 per cent uplift to GMS funding and a 0.5 per cent investment in enhanced services for 2008/9.
Last week GP revealed that NHS Employers' recommendation of a 1.5 per cent pay rise would leave three-quarters of practices on MPIG.
DoH evidence backs a similar uplift of 1.6 per cent, which it says would cover rising expenses. The DoH evidence says GPs have retained too much of their income as profit and any further income should be linked to new work.
The GPC says a pay rise of at least 4 per cent is required to counter growth in expenses. Its evidence to the DDRB says that by the end of 2008/9 soaring expenses will have cut practice income by 10.6 per cent since 2005/6.
GPC negotiator Dr Peter Holden said: 'Staff pay is by far the biggest element of expenses. Two-thirds of expenses are now staff pay. It used to be 33-40 per cent. That nails the jibe that we didn't invest - we damn well did.'
Laurence Slavin, from medical accountants Ramsay Brown and Partners, predicts that a practice with 8,000 patients could see expenses rise between £19,307 (based on inflation of 3.75 per cent) and £24,543 (5 per cent inflation) next year.
GPC chairman Dr Laurence Buckman said he hoped that, as well as the 3.5 per cent uplift, PCTs would use surpluses to invest an extra 0.5 per cent in enhanced services.
However, the GPC appears to have little faith that enhanced services will be increased. GPC deputy chairman Dr Richard Vautrey said enhanced services cash had 'not materialised time and time again' and was not a reliable source of income.
Dr Buckman said the DoH must award a pay rise if it was serious about reducing practices' reliance on MPIG.
'If getting people off MPIG is central to your policy, the way you make it happen is to put a lot of money in. You can't argue that it is important and not put money into it,' he said.
The DoH and NHS Employers plan to investigate which practices have MPIGs and why to inform further steps to scale down reliance on the top-up.
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