The review will go far beyond this year's delayed test results
The Conservatives say they are setting up a commission of inquiry into the future of school exams in England.
It will examine how to restore confidence in the system so testing in schools, and exam qualifications, "are rigorous, robust and relevant".
An official inquiry is being held into delays in the marking of this year's national curriculum or "Sats" tests.
But Tory leader David Cameron said the firm running them, ETS, must not be allowed to continue doing so next year.
Mr Cameron told his regular news conference that ETS should also forfeit any payment it was due.
"We must reform the way the Qualifications and Curriculum Authority (QCA) operates and the way the government operates to make sure that those who mess up like this do not walk away with large sums of taxpayer's money that they simply haven't earned," he said.
"We cannot let the company which has presided over this fiasco be responsible for next year's tests."
ETS is in the first year of a five-year contract.
Shadow children's secretary Michael Gove has asked former Imperial College Rector Sir Richard Sykes to head the inquiry.
Mr Gove said testing was important for measuring how individuals, schools and ministers were performing.
On Friday the tests contractor ETS said 29% of the results of English tests taken by 14-year-olds had still not been issued.
It said 93% of their maths results were available and 91% of science.
About one in five primary schools had not received a full set of marks.
Mr Gove said: "The debacle over Sats this year has badly damaged the confidence of parents, teachers, universities and employers in the current system of testing.
"It is vital that we have a testing and examination system which enables our young people to compete with the best in the world."
A party spokesman said Sir Richard's report would apply only to England, but he could draw on experiences from elsewhere in the UK and/or abroad.
He would examine how best to ensure that testing served three purposes: assessing individual pupils' progress, making schools accountable to parents and measuring the effectiveness of national policy.
It would also consider how to address people's concerns that existing qualifications "do not provide the best preparation for the world of work or further and higher education".
Schools Secretary Ed Balls has written to the chairman of the Commons schools select committee to say he shares the frustration and anger of teachers, children and parents about the delays.
He said the contract had been drawn up by the Qualifications and Curriculum Authority "at arm's length from Ministers".
Mr Balls said the current system was "not set in stone", with a pilot of new single level tests being held over the next year.