Michael Gove launched a stinging attack on Welsh education minister Leighton Andrews as he ruled out ordering an independent inquiry into the GCSE English grading fiasco.
The Education Secretary called Mr Andrews' decision to order an exam board to re-award its English language GCSE "irresponsible" and said it was a "regrettable political intervention". He insisted Mr Andrews had taken "decisive action in the wrong way" accusing the minister of damaging Welsh children's education, and attempting to shift the blame.
Giving evidence to the Commons education select committee Mr Gove also said it would be wrong for him to appoint an outside body to investigate the debacle.
It has been estimated that thousands of teenagers received lower than expected grades this year after GCSE English grade boundaries were moved between January and June.
On Tuesday, Mr Andrews ordered the WJEC board, which sets GCSE exams in both England and Wales, to re-award papers in the principality following a Welsh Government review.
But England's exams regulator, Ofqual has insisted it would be inappropriate for exams to be regraded. Its inquiry into the fiasco concluded that January's GCSE English assessments were "graded generously" but the June boundaries were properly set and candidates' work properly graded.
WJEC has called on regulators in the two nations to come to a "common view" on how to proceed, arguing it has been put in the "difficult and unexpected position" of being given different instructions from each.
Pat Glass, Labour MP for North West Durham, told Mr Gove the situation is "not going to go away, children's lives have been damaged by this". She said: "Are you prepared to have years of this being mired in the courts, because it's not going away Secretary of State."
Mr Gove said he recognised there are some people considering a legal challenge. He added: "I think this situation would only worsen if I were to do what, for example, the Welsh education minister has done and decide that I know better than exam boards how to mark the papers. I think he has taken decisive action in the wrong way. Being decisive is one thing, being right is another and I'm afraid that he's in the wrong and the Welsh children are suffering."
Responding to Mr Gove's comments, Mr Andrews said that the Education Secretary had "got a number of basic things wrong". He said: "Clearly it suits him to try and turn the deepening crisis in England into a political spat with Labour in Wales - but we are going to stick to the facts and the core issue at hand. The pupils affected by this mess deserve straight answers, not political game playing."