The London borough of Bromley is bracing itself for the biggest increase - more than 1,000 per cent - in the number of secondary schools it will be responsible for this autumn.

The council is now reviewing the structure and organisation of its education department and planning to employ more staff.

Essex, which is facing a 200 per cent rise, said councils currently funded to support locally-managed schools could not take on ex-GM schools without more cash.

And in Kent, facing an increase of almost 130 per cent, councillors have been demanding a pound;1 million share of what it costs to run the Funding Agency for Schools - the quango which administers finance for opt-out schools.

Dave Shipton, policy officer for Kent’s local management scheme, said: “We are taking on all this extra responsibility for no extra money.”

Other councils facing increases of 100 per cent or more are Trafford, Peterborough, Milton Keynes, Thurrock, Calderdale, Reading, Gloucestershire, Southend and the London boroughs of Brent, Hillingdon, Wandsworth, Sutton and Lambeth.

The abolition of the 1,196-school opt-out sector in September heralds a new education landscape comprising foundation, voluntary and community schools.

Opted-out schools are discussing their new status now and the majority are expected to become foundation schools, the closest to their present position.

As such, they will continue to employ their own staff and keep their admissions arrangements.

But their funding will be channelled through their former local authority, which will also be responsible for monitoring their performance, setting targets and providing support.

Many schools are expecting a rough ride as old scores are settled. Some heads of local authority schools refuse to be even be in the same room as GM heads.

The GM Schools Advisory Committee is compiling a dossier to be presented to ministers at the end of next month and Pauline Latham, its chairman, said:

“There are major problems ahead. It is not going to be smooth sailing.

“Any school could have become GM. We have not chosen to become foundation or voluntary schools. That decision was made on our behalf. We have moved on but they can’t.”

She said councils did not need to recruit lots of extra staff for the new role. “It doesn’t have to be heavy-handed. GM schools don’t need council officers going in and telling them how to do things.”

Graham Lane, education chair of the Local Government Association, said there would be difficulties for councils. Those who needed staff should make sure they had the cash available: “Don’t delegate everything to schools,” said Mr Lane.

A spokesman for the Department for Education and Employment said: “The additional money announced in the comprehensive spending review of pound;16 billion for England is the largest-ever single investment in education. This takes account of the additional responsibilities authorities now have to face.”