Members of the MSF union are threatening a revolt over their leaders' apparent decision to abandon its opposition to the private finance initiative and publicprivate partnerships, agreed at its annual conference last month.

A statement from the national executive committee earlier this month argued: 'After extensive discussions. . . with government, we believe the aspirations of both government and MSF can be met.'

And last week, general secretary Roger Lyons went further, saying:

'We endorse the prime minister's plan of conditional introduction of private service provision to improve services in the NHS.'

A memo from MSF head of health Roger Spiller, seen by HSJ, warns union officials that 'a campaign is developing critical of the decision taken on PPP/PFI'.

It urges them to ensure support for the national executive statement: 'Our positive role with the DoH and SoS [secretary of state Alan Milburn] in particular and their support for our agenda is dependent on MSF being positive.'

London delegate to the health national advisory council Frank Wood said: 'It is quite clearly backtracking from conference policy.'

He said London health delegates had agreed a counter-position to the national executive, reaffirming 'that MSF is opposed to privatisation of the public sector'.

But an official MSF spokesperson insisted there was 'no real contradiction' between Mr Lyons' remarks and conference policy.