Michael Gove says A-levels should be "protected" from politicians
The Conservatives want politicians to withdraw from interfering with A-levels and other exams in England.
Shadow Schools Secretary Michael Gove wants universities, learned societies and exam boards to become responsible for what is taught.
It would mean "ministers cannot meddle with these crucial tests for their own ends," says Mr Gove.
Schools Minister Iain Wright said the Tories were "confused" as there was already an independent regulator.
"Michael Gove is either confused or making it up as he goes along. We recently established Ofqual as an independent regulator of exam standards, which reports directly to parliament rather than ministers," said Mr Wright.
"Michael Gove also seems to have forgotten that his own leader last year pledged to abolish the QCDA, the arms-length body responsible for the curriculum and Sats, in order to bring it under the direct control of politicians."
In a speech to the Royal Society, the Conservatives' schools spokesman called for a clearer division between ministers and the exams system.
"We must ensure that A-levels are protected from devaluation at the hands of politicians," said Mr Gove.
"The institutions with the greatest interest in maintaining standards at A-level are those which receive A-level students - our universities.
"The individuals with the keenest interest in ensuring A-levels require the depth of knowledge necessary to flourish at university are our teaching academics.
"So we will take control of the A-level syllabus and question-setting process out of the hands of bureaucrats and instead empower universities, exam boards, learned societies and bodies like the Advisory Committee On Mathematics Education with the task of ensuring these qualifications are rigorous," he said.
Mr Gove also promised that a Conservative government would "overhaul the national curriculum in the core subjects of English, maths and science so that changes can be introduced from September 2011".
And he said that pupils should be able to study the three science subjects - physics, chemistry and biology - in a "proper, rigorous fashion" rather than in a "hybrid" form.
And he says that state schools should be allowed to take the international GCSE, taken by pupils in some independent schools.
The proposals were welcomed by the exams group, Cambridge Assessment, which said it believes "education should not be hindered by unnecessary regulation and political interference".
But exam boards, operating as commercial organisations, have faced questions about maintaining sufficient rigour.
Last week, the Science and Learning Expert Group called for more demanding GCSEs and A-levels and regulation of private exam boards.
They wanted more control over private exam boards to "prevent competition between them leading to lower standards".