MPs say rushing into separate exam systems in Wales, England and Northern Ireland would be "regrettable."
A new report from the House of Commons Education Select Committee urges all three nations to continue to run GCSEs and A-levels, and ministers should "do everything possible to bring this about."
Last month, the Education Secretary Michael Gove wrote to the Welsh and Northern Irish Education ministers saying that 'the time is right' for the exam systems in Wales, England and Northern Ireland to separate.
Welsh Education Minister Leighton Andrews has said there will continue to be GCSEs, A-levels and AS Levels in the exam system here.
Details of the most radical overhaul of GCSEs in England for a generation will be announced later today.
Plaid Cymru's Education spokesperson Simon Thomas says the priority now must be to ensure Wales-only exams are not seen as 'second rate' in relation to England's. He says they must be monitored by a powerful, independent regulator.
Education Minister Leighton Andrews says the Michael Gove letter means 'the days of three country regulation [of exams] are over.' He says the priority is now to ensure that a future Wales-only system has the confidence of students, schools, universities and employers.
Leighton Andrews also says that he's been in contact with his counterpart in Northern Ireland to look at the possibility of a joint regulatory system.
Plaid Cymru's Education spokesperson, Simon Thomas, says the Gove letter has highlighted the need for urgent action by the Welsh Government to ensure confidence in an increasingly distinct Welsh exam system.
The Education Minister should 'stop having spats on Twitter' and concentrate on improving education standards, according to the leader of the Welsh Liberal Democrats. But Kirsty Williams said she's 'relaxed' as a politician and as a mother, about the prospect of different exams in Wales and England.
Her comments follow a letter sent to Leighton Andrews by the Education Secretary Michael Gove suggesting that a separation of the exam system was now inevitable because of changes being looked at in the two countries. Kirsty Williams said it's 'perfectly possible' to have a credible Wales-only exam.
But she attacked as 'unbecoming of a government minister' the decision of Mr Andrews for taking to Twitter to respond to criticism from UK Government sources. She said 'sometimes it seems Leighton Andrews would rather spend his time having a row on twitter than concentrating on his job.'
Education Minister Leighton Andrews will face an urgent question in the Assembly on the letter from Education secretary Michael Gove. The Presiding Officer Rosemary Butler has allowed the urgent question to be raised in this afternoon's session.
A senior Plaid Cymru politicians says different exam systems in Wales and England could lead to higher standards in Wales. Rhodri Glyn Thomas was responding to the news of Education Secretary Michael Gove's letter to his Welsh and Northern Irish counterparts suggesting a split is on the cards.
The Plaid AM said he 'would welcome the opportunity to separate the exam system in Wales' from that of England and he rejected claims that it could lead to reduced standards, saying
The Education Minister, Leighton Andrews AM, has taken to Twitter this morning over the future of exams in Wales.
Michael Gove's letter as reported in the Guardian contains the suggestion that Wales and Northern Ireland may have to give up the titles 'GCSE' and 'A-level' if the systems are to diverge. The Welsh Government's official response is terse.