By Gary Eason
Education editor, BBC News website
A head teachers' leader has called on the government to clarify its new target for secondary school league tables in England.
John Dunford says schools need an explanation
The Department for Education and Skills has said it wants five good exam grades including English and maths GCSEs.
But in written guidance to schools it has said literacy and numeracy skills tests might also count.
The general secretary of the Secondary Heads Association, John Dunford, said clarification was needed urgently.
Dr Dunford said he thought the numbers of pupils currently doing non-GCSE equivalent English and maths qualifications, such as Key Skills and Basic Skills for adults, were "pretty small".
But he said this might increase if schools saw them as a way of raising their crucial "five A* to C" scores, as the government's guidance suggests.
"I think that the situation needs clarifying and I will take steps to get it clarified," Dr Dunford said.
He would raise it with the Department for Education and Skills (DfES) as soon as possible.
People needed to know what the situation was before schools began putting in place courses based on "equivalent" qualifications, he said.
Some schools are already intending to do this.
A number of local education authorities have said the situation is confused.
And Sir Mike Tomlinson, whose review of secondary schooling prompted the government's focus on English and maths skills in the GCSE tables from next year, has also said he thinks there is confusion.
A spokesman for the DfES said that if Dr Dunford wrote to it, it would respond in due course.
He declined to elaborate on what it would say.