GCSEs: Politicised exams in England hit Wales - minister
The Welsh education minister has complained that the exam system is being "politicised" in England amid a fall in top grade GCSE passes.
Leighton Andrews says he believes exam boards had been pressured to mark more harshly, which Whitehall denies.
He accused UK Education Secretary Michael Gove of bringing politics into the exam process.
Mr Andrews added that he had asked his officials to review the results for GCSE English as a priority.
The latest GCSE results show a fall in the pass rate in the top grades across England, Wales and Northern Ireland for the first time since the exams replaced O-levels and CSEs 24 years ago.
Teachers have claimed examination boards have marked pupils too harshly, especially in GCSE English.
Mr Gove has denied that pressure had been put on exam boards to change grade boundaries amid criticism that exams were becoming easier every year.
But Mr Andrews said Mr Gove's recent pronouncements on the rigour of exams were having an impact.
"I think it's a shame that we're seeing politics brought into the exam process by the Secretary of State for Education in England, Michael Gove," he told BBC Wales Today.
"We want a system that works for the young people of Wales, and now we need to review what needs to be done to deliver that."
Earlier, he told BBC Radio Wales: "When Michael Gove says jump, the head of (exam regulator) Ofqual says 'how high'.
"We need to look at the integrity of the Welsh system and whether we can have confidence in the Welsh system if political decisions in London are going to undermine performance in Wales."
Mr Andrews said particular difficulties were being caused by a new combined GCSE English exam taken by many schools in England, which he had not approved for Wales.
"We care about high standards in Wales," he said.
"We believe it is important that learners follow the fuller programme of language learning that is covered by GCSE English language.
"What is clear now is that we are no longer comparing like with like when looking at results in Wales and England."
While Scotland has long had its own education system, ministers in Wales and Northern Ireland have become increasingly unhappy with Mr Gove's lack of consultation over policy announcements.
"Last month the Northern Ireland Education Minister (John O'Dowd) and I met and then wrote to Michael Gove because of our concerns at his unilateral statements and actions on GCSEs and A-levels," said Mr Andrews.
"It is clear that we now need to consider whether our own system can be in hock to 'Gove-it-alone' policies.
"These issues will be considered in relation to our current review of qualifications."
Mr Gove has spoken of his desire to restore O-levels in England in place of GCSEs, with less academic pupils taking exams similar to the old CSE.
While the review in Wales continues, Mr Andrews has already said Wales will not return to an O-level style system.
Ministers will also reconsider the role of WJEC - formerly the Welsh Joint Education Committee - and whether it should continue setting exams for schools in England as well as Wales.
A Department for Education spokesman said it was "down to the Welsh and Northern Irish administrations to decide how to run their education systems - and down to us to do what is best for English students".