Teenagers without C grades or higher in English and Maths will have to study for GCSEs in the subjects, but will be allowed to take other qualifications alongside them, said the Department for Education.
The English and Maths results of 16-19-year-olds who did not gain these key GCSEs will also be reported in annual school league tables, the department said.
Education Secretary Michael Gove said it was in the older teenagers best interest to remain in education to attain C grades, even if they were old enough to legally finish school.
Good qualifications in English and maths are what employers demand before all others. They are, quite simply, the most important vocational skills a young person can have. Young people must be able to demonstrate their understanding of these subjects.
More top news
The president of Sierra Leone has defended his reaction to the Ebola crisis, telling ITV News it will be contained by the end of the year.
James, who says police are stopping him on his walk to work because he looks like a fugitive, has started an internet campaign to buy a car.
Two American priests have become an internet sensation after a YouTube video of them having a dance-off was watched nearly 300,000 times.