Guidance is also to be sent to all local education authorities to help raise education standards among all ethnic minority children.

The review comes as the extent of under-achievement among pupils from ethnic backgrounds, particularly black boys in Wales, is revealed in comprehensive data for the first time.

Figures comparing academic achievement and ethnic background across Wales for 2005 show that pupils from some ethnic backgrounds perform well below the Welsh national average in teacher assessment tests throughout all the key stages at school.

More than pound;8 million is provided every year, with three annual grant schemes intended to promote achievement and support asylum-seeking and Traveller children. But some schools claim the grants are difficult to access and money is not provided soon enough, when pupils first start attending schools.

An Assembly spokesperson said the present grant system was being looked at “closely”, to ensure maximum outcomes. “It is important to note that the very small numbers of pupils from ethnic minorities in Wales make it difficult to draw conclusions from a single year’s data such as this,” he said. “We will gain a clearer picture when we are able to aggregate several years’ data to form a more robust picture.”

The new figures show that 63.3 per cent of black 7-year-olds passed core subject indicator teacher assessments in 2005, compared with 81 per cent of white pupils. By KS4, pass rates of black pupils had dropped to 21.6 per cent. Pupils from white and Chinese backgrounds were the only groups to perform well above the national average.

Jane Davidson, minister for education, lifelong learning and skills, recently said that raising the achievement of ethnic minorities, particularly black boys, was a key target for the Assembly government in 2007.