White British schoolboys from working-class families are falling behind their classmates at a greater rate than previously thought, UK government figures showed yesterday.

Less than a fifth (19 per cent) of those eligible for free school meals - an indicator of poverty - achieved at least five grade Cs at GCSE, including English and maths. In comparison, more than half (50.8 per cent) of white British boys not entitled to the meals attained the marks, including the two core subjects - a gap of 31.8 percentage points.

This has grown from 29.8 percentage points in 2006.

The Department for Children, Schools and Families (DCSF) announced the revised figures after adding 5,700 results omitted from the original study of 579,000 pupils.

Provisional statistics, published in December and withdrawn last month, had suggested 19.4 per cent of boys were achieving the standard, compared with 51 per cent of those who do not receive the meals.

The new figures showed the gap had widened slightly, with poorer pupils behind their richer classmates overall.

They showed 26.6 per cent of all pupils entitled to the meals got five A*-C grades, including English and maths, compared with 54.2 per cent of those who do not.

Provisional figures had placed the total at 26.9 per cent and 54.4 per cent respectively.

For white British girls, 24 per cent of those entitled to the meals achieved the grades, compared with 57.8 per cent of those not.

The study showed 54.4 per cent of girls got five A*-C grades, including English and maths, compared with 47.1 per cent of boys.

The highest achieving ethnic groups in terms of gaining at least five A*-C grades were Chinese (71.6 per cent), Indian (67 per cent) and mixed white and Asian (62.3 per cent).

Overall, 93.7 per cent of girls got at least five grades between A* and G, compared with 90.4 per cent of boys. Schools Minister Vernon Coaker said: "This year has seen huge sustained rises in GCSE results with more children across the country achieving good results, regardless of ethnicity, class or special educational needs.

"The largest overall improvements over the last 12 years have been in disadvantaged areas - thanks to Academies and City Challenge programmes.