By Gary Eason
Education editor, BBC News website
Only one in every six black Caribbean boys meets the government's new league table benchmark for secondary schools.
There is already concern at the underachievement of black boys
Ministers have underlined their commitment to focusing on the basics with a new expectation that all pupils should have good GCSEs in English and maths.
As the BBC revealed in October, GCSE-level attainment in many schools will fall - they make the grade at present, but not when English and maths are taken into account.
A Department for Education and Skills target-setting document sent to education authorities says this will have a particular impact on already underachieving ethnic minorities.
"At a national level in 2004, there was a narrowing of the attainment gap for all of the headline minority ethnic pupil groups at Key Stage 4 [GCSEs]," it says.
This was in relation to the existing league tables benchmark of five good GCSE-level qualifications in any subjects.
But the performance of minority ethnic pupils in achieving five or more good GCSEs including English and mathematics, "highlighted a different and more worrying picture", the document said.
The gap for underachieving pupils "widened considerably" in "a large number" of local authorities.
The BBC News website asked the Department for Education and Skills for the local authority statistics underlying this analysis.
It said they were "an internal piece of work, not in a publishable form".
But it has provided national statistics - which show wide variations between ethnic groups.
Overall, 40.3% of pupils in 2004 achieved five good GCSE-level qualifications including English and maths GCSEs.
This compares with the 53.7% getting five good grades under the existing measure, covering any subjects.
Chinese pupils outperformed everyone else: 62.9% hitting the new benchmark
The figure for white pupils was 40.9%. Overall it was 41.5% for Asian pupils, but with marked differences between Indian (54.1%) and Pakistani (30.8%) and Bangladeshi (32.1%) youngsters.
Among black pupils overall the figure was 26.4% - but for those from black Caribbean backgrounds just 22.8% overall and 17% of the boys.
The target setting document says the rate of progress in narrowing achievement gaps varied considerably across local authorities, with not all demonstrating the upward trend seen at a national level.
"In particular, we continue to be concerned by the slow progress in raising the attainment of black Caribbean pupils (especially boys) and for Pakistani and Bangladeshi pupils outside of London."
It says the national data can obscure the underperformance of some communities.
So it urges local authorities to "bring on groups such as Somali, Turkish and Portuguese pupils for whom there is considerable qualitative research pointing at underachievement".