Image caption The qualification for school leaders is to be overhauled and made optional

The qualification currently required for head teachers in England's state schools will no longer be compulsory, the government has announced.

Head teachers have attacked the change as a "backward step".

In theory it would mean that a head teacher could be appointed without any teaching qualification.

Schools Minister Nick Gibb said governments needed to "step back and let heads get on with running their schools".

Under the government proposals the National Professional Qualification for Headship (NPQH) is to be revised - and from next year will cease to be compulsory.

As head teachers are not required to have a teaching qualification, it means that non-teaching staff, without a NPQH, could become state school head teachers.

Leadership training

Brian Lightman, general secretary of the ASCL head teachers' union, described the move to a voluntary qualification as detrimental to raising the status of heads.

"Having a national, professional qualification for head teachers has helped to raise the profile and status of school leadership in this country and it is something we should be proud of," said Mr Lightman.

"We regret that the government is making this qualification optional at a time when there has never been such great need for highly-trained school leaders."

The National Association of Head Teachers said that it believes that "all head teachers should have Qualified Teacher Status".

But general secretary, Russell Hobby said that the NPQH "should be the standard for all aspiring heads. We think if it is good enough, it will be, mandatory or not".

The NPQH qualification, introduced in 1997, had been part of a drive to professionalise the role of running schools, providing specific training for people wanting to become heads.

Among those currently in headships, 58% have the NPQH, which two years ago was made a compulsory requirement for new head teachers.

But the schools minister has announced plans to make the qualification voluntary - promoting autonomy rather than regulation - and to have the content of the training revised by the National College for School Leadership.

There is a promise that the "bar for entry and assessment for the qualification will be raised".

The revised training, which will begin from September 2012, will focus on pupil behaviour, leadership skills and managing teacher performance.

Placements and school-based training will be extended and there will more emphasis on support from line managers, who can "sponsor" a would-be head teacher within their staff.

Mr Gibb said: "We want to create a qualification for those about to become head teachers that will help them develop the key skills needed to take on this challenging and rewarding role.

"It will start them on the journey to becoming outstanding lead professionals. We also want to ensure the NPQH remains a highly regarded and sought-after qualification."