GPC deputy chairman Dr Laurence Buckman said that the threshold changes would be based on previous levels of achievement so should not cause practices any problems.
'Threshold changes are based on last year's figures so they are mostly things GPs are doing anyway. For most this will just be a data collection exercise next April,' he said
'For example, if a threshold was 25 per cent last year and everyone scored 40 per cent, it has gone up to 40 per cent. Nobody should have to do more work.'
The changes, along with the new quality indicators and domains already announced, will come into effect from 1 April. GPs are concerned that they have no details of the revised framework as yet.
However, Dr Buckman said GPs should not see the six weeks from now until April as a preparation period, because data would not be collected until April 2007.
'The old markers will continue until 31 March so you won't want to knock them off anyway, and nothing actually happens this April - it just starts then,' he said.
GPC negotiator Dr Mary Church agreed that GPs should not worry about changes to the framework: 'The thing is evolutionary. It was always expected that thresholds would rise.'
NHS Employers is currently looking at the proposals. A final deal will be thrashed out between the two negotiating teams.
Dr Buckman said that final sign-off for the deal would not happen until every part of the contract had been agreed as a 'package of proposals' and this was 'very unlikely to happen this week'.
Dr Church added that there had been 'one or two problems' but would not specify what they were, adding that they would 'hopefully be resolved soon'.
A spokeswoman for NHS Employers said: 'The guidance is a comprehensive, technical document and we have had to do a considerable amount of work to get it ready. It is important that we spend the time ensuring that it is right first time.
West Midlands GP Trevor Rees was concerned about the lack of quality guidance.
'I am concerned it's being changed and we are doing more for no more money,' he said.
Meanwhile, the four clinical directed enhanced services (DESs) being negotiated in Scotland will cover identifying unmet patient need in cardiovascular care, learning disabilities, improved liaison with carers and ensuring speedier cancer referrals get through the system quickly. Details are still being negotiated.
In Wales, the GPC is 'close to sign-off' for DESs for access, similar to that agreed in England, and an IT service similar to quality information payments, one of the original DESs for note summarising.
A DES for learning disability looks probable, while talks for one on mental health are 'still progressing'.
Two clinical DESs in Northern Ireland have not yet been agreed.