The measure was portrayed as a sop to rebel Labour backbenchers. Critics said it undermined the Government’s pledge to free schools from local authority control.

John Dunford, general secretary of the Association of Schools and College Leaders, said: “It is a far cry from the Prime Minister’s vision of schools being more independent from local authorities.”

In fact, the draft guidance announced at the NASUWT conference last week, and to be confirmed if the education Bill is passed later this year, appears faithful to ministers’ original vision of a shift in role for councils from providers of schools to regulators.

Moreover, many of the powers, which do not apply to academies, already exist. They mean that failing or coasting schools will have 15 working days to make improvements spelled out in warning notices issued by councils.

Failure to comply gives an authority the immediate right to intervene in one of four ways:

* to take control of the school’s budget;

* to appoint additional governors;

* to install an interim executive board of handpicked governors;

* to require the school to collaborate with another school, college or other organisation, or to enter a federation.

To issue a warning notice a council must have what the guidance describes as unequivocal evidence of one of three scenarios.

The first - pupil performance is unacceptably low and likely to remain so without intervention - has been extended to include coasting schools.

It is not enough just to look at absolute attainment levels. They must be considered in the context of pupils’ prior attainment.

The second is where there has been a serious breakdown in a school’s management or governance likely to lead to lower standards. Ruth Kelly, Education Secretary, won applause from NASUWT delegates in Birmingham when she revealed this category includes a failure to implement the workforce agreement or poor management of staff.

Finally, a warning notice can be triggered where pupil or staff safety is jeopardised, for example if there is a sudden drop in standards of behaviour.

But there are important qualifications. The guidance says warning notices are unlikely to be needed where a school is working positively with an authority or where there is evidence that it is making progress with a school improvement partner.

In stronger terms, it says notices should not be issued where:

* school leadership has changed within the last three terms;

* an Ofsted inspection is being brought forward;

* only a single year of performance data shows a decline, unless it is directly attributable to poor management;

* the school acknowledges the problem and is working with its school improvement partner or a mentor head to address it;

* the school is rectifying problems uncovered by a grade three (satisfactory) Ofsted report.

Where a warning notice is issued by an authority, the school has 15 days to appeal to Ofsted, which may then inspect the school.

Inspectors can either uphold the appeal overturning the warning notice, or back the authority by placing the school in special measures or issuing their own formal notice to improve.

The caveats did not prevent Mr Dunford from saying the guidance was “extremely worrying”.

“With local authorities constantly anticipating their own next Ofsted inspection, they want to be seen to be taking action to improve schools,”

he said. “This often results in unnecessary interference in schools.”

But Chris Keates, general secretary of the NASUWT, said: “What have heads got to fear if they are managing the school workforce fairly?”

* william.stewart@tes.co.uk