The Conservative Party has proposed significant changes to the standard attainment testing system (Sats).
By testing children in the first year of their secondary education and not while in primary school, the party hopes to reduce duplication and improve standards.
Shadow education secretary Michael Grove told BBC1's Andrew Marr show: "We want a system of testing which allows us to accurately measure how well individual children are doing and also to accurately measure how schools are doing."
He argued that moving the exams into secondary schools will give primary school teachers and their teaching assistants
more time for teaching.
Teaching unions have been divided on the matter. Members of the NASUWT recently gave their approval of the tests, arguing that without them teachers' workloads would increase, while the National Union of Teachers' delegates voted against Sats.
The tests are currently sat at the end of key stages one, two and three, when children are aged seven, 11 and 13 respectively.