A faultline opened up between the Labour leadership and the trade unions on the future of the NHS last night over the text of the motion to be debated by conference tomorrow.

Delegates were engaged in a marathon session to decide whether to lambast or praise the government's record on the NHS. Unison, led by Dave Prentis, and backed by the T&G, Amicus and the GMB, are fighting to keep a highly critical motion condemning NHS cuts. They are calling for a halt to a controversial payment by results system, and for an end to the privatisation of services like NHS Logistics, which provides everything from blankets to bedpans. In the biggest outbreak of industrial unrest in the NHS for 20 years, health workers last week went on strike in protest at the government's decision to privatise NHS Logisitics.

Ranged against the unions were more than a dozen constituency associations including Tony Blair's association, Sedgefield, and the Leigh constituency of health minister Andy Burnham.

This motion praises the government's health reforms and says that half the services, particularly those provided by GPs, are already in the private sector.

Last night neither side seemed to want to give an inch, with union officials warning that there would be a "bloody battle" and they were not having their motion "toned down" by the leadership.

While negotiations were going on, the TUC general secretary, Brendan Barber, headed a union rally to defend the NHS with Unison and Amicus.

The party leadership offered a small olive branch by saying that future NHS reforms would be referred to the party's policy forum but refused to back down over the privatisation of NHS Logistics.

The leadership were more confident that they would get more support from today's national executive committee. Denis Skinner, one of the biggest opponents, is ill and unable to attend.