GP leaders warned the cuts would be 'catastrophic', with thousands of practices destabilised. The warning came as it emerged some PMS practices face additional cuts this year as local contract reviews continue, despite commitments from NHS England to 'pause' changes ahead of the wider contract overhaul from 2014.
Dr Buckman called for an immediate halt to local PMS reviews and urgent clarity for all GPs concerning funding for the next eight years.
From April 2014 GMS practices in receipt of MPIG will lose a seventh of their correction factor payments each year for seven years, to cut variation in core funding. Funds saved from the MPIG cuts will be recycled back into global sum payments.
The GPC is pushing for funds saved from PMS to be reinvested across all practices, to soften the blow of removing MPIG. But the GPC fears this funding will be diverted elsewhere in the NHS.
Dr Buckman warned this would 'lead to this money being lost to general practice, seriously destabilising thousands of practices'.
Some PMS practices face additional income cuts ahead of the 2014 overhaul. NHS England confirmed to GP that some local PMS reviews inherited from PCTs were continuing.
A spokeswoman said some reviews were 'so close to completion it would have been inappropriate to pause them'. No new reviews will be initiated during 2013, she confirmed.
GP leaders hit out at plans to press ahead with the reviews and said it was 'staggering' that practices had not been clearly informed about whether changes would go ahead.
NHS England asked its area teams to 'pause' reviews in a note published on 10 April.
GPC negotiator Dr David Bailey warned that equalising GMS and PMS funding was complex.
He said GMS practices received about £67 per patient on average, with the PMS average about £10 higher. But he warned that PMS baseline funding for many practices covered services that were not core GMS work. 'Some funding in PMS baselines is in effect for enhanced services,' he said. 'You would have to strip that out before trying to level out PMS and GMS funding.'
Dr Bailey agreed that if the extra £10 per patient PMS practices receive was stripped from primary care, it would wipe about £200m from practice funding in England.