By Hannah Richardson
Education reporter, BBC News
Primary school league tables exposed under-performance
Poor performing primary schools in England could be forced to work closely with more successful ones in a crackdown on standards.
Local authorities are being told to draw up action plans for 1,400 schools where fewer than 55% of pupils reach required levels in English and maths.
Children's Secretary Ed Balls has also written to 12 local councils with the highest proportion of troubled schools.
But he has refused to say which areas are being ear-marked for special help.
This unwillingness to identify which local authority areas are being targeted for special help comes after the Secretary of State faced criticism for allowing struggling secondary schools to be "named and shamed" in the National Challenge programme last year.
That highly controversial move threatened more than 600 schools that fell below a GCSE threshold with takeover or closure if they failed to improve.
Mr Balls said that primary schools that had been consistently below the "floor target" for English and maths results for four years or more, should be targeted for special help.
"It's not an excuse to say most of our primary schools are doing really well but of course you wouldn't expect that primaries on that side of town to be so good," he said.
He wanted to provide a "rocket-boost" to standards by asking local councils to identify which schools could benefit from help from the "great and good" schools nearby.
These schools would be pre-accredited as schools in a position to offer help to others in difficulties. They would get an extra £75,000 to help with this.
Meanwhile local authorities would be encouraged to use their power to force schools to "federate".
All schools should have access to specialist teachers in English, maths and modern languages. But these could be shared between schools that were working closer together, Mr Balls added.
Mr Balls wants an action plan from the 12 local authorities with the most problems by February next year. Action plans would be expected from all local councils by March.
He added: "If we feel that local authorities are not gripping the agenda then sanctions were something that we could look at as well."
These might include sending advisers from the Department for Children, Schools and Families into local authorities and encouraging more federations between schools.
Federating has also been identified as a means of saving money. Mr Balls wants schools to save up to £750m by sharing resources, management teams and through smarter procurement.
The plans are part of the department's efforts to help schools make savings against the backdrop of over-stretched public finances.
This week's primary school league tables showed how England's schools were getting worse.
Nationally, the average attainment in both English and maths is 72% - down one percentage point on last year, against a target of 78% by 2011.
Christine Blower, general secretary of the NUT, said more funding for education was always welcome.
She added: "Ed Balls seems determined to replicate the mistake he made with his National Challenge for secondary schools - that of setting arbitrary floor targets.
"Schools in the toughest areas may add enormous value to their pupils' achievement but if they don't hit these targets, their success will be turned into government-deemed failure."
Dr Mary Bousted, general secretary of the Association of Teachers and Lecturers, said: "Teachers do not need more people watching and reporting on what they do. What they need is proper professional support to reflect on, share and increase excellent classroom practice."
Shadow children's secretary Michael Gove said the government had completely run out of ideas.
"In the week that official figures show the number of underperforming primary schools has increased, all Ed Balls can come up with is a letter to local authorities with a vague request asking them to improve."