Parents will have a right to appeal to local councils over the tuition
Children falling behind in the Three Rs in England are to be given a right to one-to-one catch-up classes.
All children should leave primary school able to read, write and count, Gordon Brown told delegates at his party's conference in Manchester.
And he pledged: "Any child who falls behind will not be left behind."
From 2011, children aged seven to 11 who have slipped behind and are failing to make adequate progress will have a guaranteed right to personal tuition.
The Department for Children, Schools and Families said the £315m in funding that would support the scheme had already been announced by the Chancellor.
'Short, sharp bursts'
This would be handed down to local authorities who were to be responsible for identifying and employing tutors who would work in schools on a one-to-one basis with struggling pupils.
Parents would also have a right to appeal to local councils if they felt their children should be eligible for the scheme but had not been identified as such.
The scheme would be based on the existing "making good progress" pilots which offer one-to-one support for children in the last years of primary school and early years of secondary school.
These have worked as short, sharp bursts of intensive one-to-one tuition on top of normal schooling. Typically children have been signed up for 10 hours of personal tuition.
Classes could run either during or outside school hours, a DCSF spokeswoman said.
It is anticipated that some 300,000 pupils would be tutored in English and a similar number in maths in 2010-11.
The spokeswoman added: "Both local authorities and schools should receive more funding than is needed to deliver this entitlement; the remaining funding will be available to provide one-to-one tuition for other pupils who would benefit."
Acting general secretary of the National Union of Teachers, Christine Blower, said: "Giving personal tuition to children who need it most, whilst not a new idea, is a bold move.
"Fairness requires that children from disadvantaged backgrounds should receive the sort of help that children from wealthier backgrounds get."