Gifted pupils will be able to sit a new GCSE in further mathematics, education secretary Ruth Kelly has announced.
The new GCSE is aimed at stretching the most able pupils
Ms Kelly said the new exam would ensure the most able were fully challenged.
The Department for Education said the further maths GCSE was expected to be piloted in schools from September 2007.
The announcement comes as ministers are reforming GCSEs so that candidates will not be able to get a grade C in English and maths without mastering basic literacy and numeracy skills.
The reforms are in response to employers' complaints that even well-qualified youngsters lack workplace skills.
Ms Kelly gave details of the new qualification at a conference of maths specialists in London on Wednesday.
"We have decided to develop an additional GCSE in further maths to complement the existing qualification," said Ms Kelly.
"This will be a major step towards ensuring that all schools prioritise mathematics at Key Stage 4 (GCSE level) and that the most able young people are appropriately challenged."
Sir Peter Williams, chair of the Advisory Committee on Mathematics Education, which hosted the conference, welcomed the announcement.
"Increasing the amount of maths in the school timetable by adding an extra GCSE will provide the stretch needed for the most able students," he said.
The government's exams watchdog, the Qualifications and Curriculum Authority (QCA), said the new GCSE was a "significant and very welcome development".
QCA chief executive, Ken Boston, said: "The second GCSE in further maths is intended to challenge the more able, engaging them in mathematical studies from a more abstract and structural perspective."
From September this year the general GCSE maths changes from a three-tier course to a two-tier course under government reforms.
Mr Boston acknowledged concerns from critics that the subject was being "dumbed down" after it emerged that pupils could get an A grade in these exams (which are currently being piloted) without answering any of the hardest questions.
"We need to ensure that the most able candidates are extended to the maximum capacity, and that those graded at A and A* have earned this score by genuinely achieving on questions set at that level," he said.
Shortage of teachers
But Lord Rees, President of the Royal Society, told the conference that a shortage of specialist maths teachers was threatening the UK's global competitiveness.
He said Britain should be "even more concerned" than the US about the issue.
"We need to persuade more graduates who have studied mathematics beyond A-level to enter the teaching profession and continue to provide high quality lessons and courses," he said.
"The supply of highly qualified teachers of mathematics may become even more of a problem in the future when we consider the long-term drop in the number of students who take mathematics after the age of 16."