Schools minister Stephen Timms indicated head teachers would be allowed to contract out the running of individual departments.
In a House of Commons debate, Labour MP Gordon Prentice accused him of introducing the 'bizarre' plans without consulting the party.
Mr Prentice's attack on the government follows condemnation from teaching unions, which accused ministers of seeking to privatise parts of the education sector.
In a newspaper interview Mr Timms said schools might find it was helpful if a department was run by a contract organisation.
He added there would be examples of state sector teachers being transferred to private employers.
Tackling education secretary Estelle Morris on the subject, Mr Prentice said: 'My question is this: where did this idea come from? It was never discussed in any of the Labour Party's policy forums, it was never discussed last September at the Labour Party's annual conference.
'If we are going to get bizarre suggestions put forward at least the government may honour us by telling us who was responsible for the idea in the first place.'
Ms Morris did not say where the idea had come from, but insisted there was no question of forcing schools to hand over control.
'What I can foresee is that some head teachers may choose to do that. It would be their choice with no instructions from me in terms of the break up of the school or the department. I want to make that exactly clear.
'I have no intention of turning my back on the contribution [the private sector] can make to raising aspirations and delivering the world-class education system we want.'
A white paper outlining the next phase of school law reform is due out next week.