It is believed the new qualification will involve a one-off exam in each subject rather than modules and continual assessment.
It is also understood the changes will not come into
effect until 2015.
Labour said it supported rigorous exams but only if they did not act as a cap on aspiration.
Education Secretary Michael Gove has made it clear he thinks GCSEs should be replaced by a new and more academically rigorous exam.
Liberal Democrats have insisted there should not be what they consider a two-tier system, with a second qualification for less able students.
The coalition parties have reached agreement on change, which Mr Gove and Deputy Prime Minister Nick Clegg will unveil this week.
The government will publish a consultation on its plans for a single new qualification.
But pupils will not start studying for it until September 2015, after the next general election. The first exams would be taken in 2017.
The move would be the biggest change in the exam system in a generation.
GCSEs were introduced in the late 1980s, to replace the dual system of O-levels and CSEs, with the first GCSE exams taken in 1988.
Pass rates have gone up every year except for this one, drawing claims that they were getting progressively easier.
‘Breadth of knowledge’
The move comes amid controversy over this year’s GCSE exams in English, and whether they were too harshly graded.
This weekend, examiners in Wales are regrading English papers taken under the WJEC examining board, after Welsh Education Minister Leighton Andrews ordered a review of results on Tuesday.
Mr Gove attacked that decision, saying it would “undermine confidence” in the value of the qualifications obtained by the students involved.
Shadow education secretary Stephen Twigg said it was wrong to be thinking about changing the system while the row over this year’s grades continued.
He said: “Politicians should not set an artificial limit on the number of top grades, rather the best work should be rewarded.
“New exams should ensure that young people are prepared for the world of work and the jobs of the future. However, it is not clear how this new system will ensure a breadth of knowledge and skills and that pupils continue studying English and maths until age 18.
“There has been no consultation on these plans, rather they have been drawn up in secret and leaked to select media outlets.”
The Welsh government is consulting on whether new qualifications for 14-16-year-olds should replace GCSEs or whether Wales should follow what happens in England.
However, the Education Minister for Wales, Leighton Andrews, has said Wales will not return to O-level-style exams.
In Scotland, pupils take Standard Grades, Highers and Advanced Highers rather than GCSEs and A-levels.
source- BBC © 2012