Literacy standards have risen in the local education authorities which perform the worst in junior English tests, according to new figures.
However, individual authorities' performances reveal that they are slightly down in many of the LEAs at the top of the test tables, prompting fears that high scores will be difficult to sustain.
The statistics show how far the Government has to go before its ambitious literacy and numeracy targets are reached.
While a few authorities are within sight of targets, many only have half their pupils performing at the required standard.
David Blunkett, the Education and Employment Secretary, has promised to resign if four out of five 11-year-olds are not at level 4 in English by 2002.
Nationally, nearly two-thirds of children have reached this standard, judged by last summer's tests. But only one in three authorities has achieved this national standard.
In maths the disparity between authorities is even more apparent. Maths scores slumped this year, partly due to the introduction of a new mental arithmetic test.
The Government wants three in four children to be at level 4 in maths by 2002. However, only one in 20 authorities is anywhere near this level. More than one in 10 has less than half the pupils at the required standard.
Announcing the new figures, schools minister Charles Clarke said the national literacy and numeracy strategies would be essential in reaching the targets.
He said: "The statistics provide important information about the extent to which our challenging literacy and numeracy targets are being met.
"The results emphasise the need for the national literacy and numeracy strategies to raise the level of our children's attainment and to help ensure those targets are met."
The city of Nottingham had the poorest results with fewer than half of its 11-year-olds reaching the required standard in English and maths. The London boroughs of Newham and Tower Hamlets followed, although their literacy scores were up on last year. The bottom 10 authorities included five London boroughs while the top 10 included the outer London suburbs of Richmond, Kingston and Windsor and Maidenhead, and the Isles of Scilly, the City of London, Surrey and Wokingham.
Tables of individual primary school performance are expected next month. They were due last year, but were delayed.