A-levels are already in transition, a report says.

The Commons education select committee called for a period of stability, during which recent reforms could be taken in.

In its report, it said the division of A-levels into AS and more advanced A2 sections in 2000 had not been "properly thought through".

Although the AS-levels were piloted, the A2 was not.

This placed "considerable pressure" on teachers, students and the system in general, the committee added.

It also asked for the exams regulator - the Qualifications and Curriculum Authority (QCA) - to be directly accountable to parliament and more independent of government.

But the three examination boards - OCR, Edexcel and AQA - should not be amalgamated.

'Transparent'

The report added: "We recommend the Department for Education and Skills (DfES) and QCA take a more pro-active role in making the examination system more transparent to parents, schools and colleges."

The report's publication follows the regrading of thousands of A-level papers last year, after allegations that grades had been lowered.

I am guardedly confident that the system will stand up this summer, due to the improvements we have made and the hard work put in by all those concerned with examinations Ken Boston, QCA chief executive

An inquiry by the former chief inspector of schools, Mike Tomlinson, found a need for clearer standards and a firmer line to be drawn between AS-levels and part two of A-levels.

But as a result, only 1,220 A-level and 733 AS-level students had their grades improved.

Liberal Democrat education spokesman Phil Willis welcomed the call for stability in the select committee's report, but added that its findings "glossed" over two key issues.

He said: "It has played down allegations that real or perceived pressure was put on the QCA and exam boards to keep down increases in A-level performance for fear of criticism.

'Shocking'

"It has failed to take adequate account of the evidence of senior examiner Roger Porkess. He called for far more papers to be re-marked.

"It is shocking that his contribution is dismissed in just a couple of sentences."

The QCA's chief executive, Dr Ken Boston, said he was confident lessons had been learned and this year's exams should run more smoothly.

He added: "I am guardedly confident that the system will stand up this summer, due to the improvements we have made and the hard work put in by all those concerned with examinations.

"However, we are still short of markers. I believe it is important that we all understand that those presenting young people for examinations also have an obligation to ensure that sufficient markers are available to mark their scripts."

A DfES spokesman said: "While we favour long-term reform, we are very conscious that we must get the balance right between long-term reform and stability.

'Over-examined'

"Pupils currently at secondary schools will continue to take A-levels and pupils, teachers and parents can rest assured that no changes will be made to AS or A2s without timely and rigorous consultation."

But John Dunford, general secretary of the Secondary Heads Association, said: "I welcome the select committee's recommendation that QCA should be more independent of the DfES.

"Many of the present problems of our curriculum and assessment systems can be traced to the lack of independence of QCA from the DfES over the last few years."

His counterpart at the National Association of Head Teachers, David Hart, added: "We are the most over-examined nation in the industrialised world.

"Excessive testing, and the whole target setting and league table bureaucracy associated with it, harms the delivery of a broad and balanced education.