But Dr Buckman told GP he believed his negotiating team had done as well as possible with a government that 'held a gun to our heads'.
The GPC chairman said he could understand people's anger, however. 'It's sad but people want to show their dismay. We've done the best we could with a government holding a gun to our heads before we came into the room,' he said.
The GPC also faces calls to take action through EU courts to challenge GP contract changes the DH plans to impose, and a warning that it risks losing credibility if it fails to address the lack of women in senior roles.
The GPC has had an all-male negotiating team since July last year, when sole female negotiator Dr Beth McCarron-Nash was voted out.
GPC negotiator Dr Peter Holden said he believed the 2013 conference, on 23-24 May, would send a strong message about rising pressure on general practice from workload and reforms.
One motion warns the 'workforce crisis in general practice is being accelerated by increasing workload and stress, and falling remuneration and morale'. It urges the DH to boost GP recruitment and retention and limit the flow of UK-trained GPs overseas.
Dr Holden said: 'I think the conference will send a strong message. I think there is a serious threat. My grave concern is, it will only be when it is too late that the nation will realise what it has lost.
'There is a serious threat that what could happen by default is, we end up with GPs as salaried employees doing the bidding of an employer.'
Dr Holden warned that a legal challenge over the GP contract was unlikely to work and all UK legal options 'would have to be exhausted first'.
LMCs will also debate calls for the GPC to negotiate the removal of the requirement for practices to join CCGs - but Dr Holden said: 'Conference wishes GPC to get parliament to rescind a law? By the time we did, the next government will be sworn in. We live in a democracy - if the government of the day passes a law, that is democracy at work.'