Gavin Williamson has been urged not to release GCSE results next week after the "unfair" downgrading of A-levels.
Many A-level students were left distraught on Thursday after some 280,000 entries were downgraded from teacher assessments.
Anger mounted on Saturday night after Ofqual, the exams regulator for England, announced that its guidance for students hoping to challenge their A-level grades on the basis of their results in mock exams was "being reviewed".
Lord Kenneth Baker, the former Tory education secretary who oversaw the launch of GCSEs in the late 1980s, told Education Secretary Gavin Williamson that publication of results should be postponed for two weeks because of the "barely explicable downgrades” of A-levels.
"I urge the education secretary to instruct Ofqual not to release the GCSEs results this Thursday as their algorithm is flawed," Lord Baker said in a statement.
"The A-level results have produced hundreds of thousands of unfair and barely explicable downgrades.
"They have helped smaller private schools but hit the brighter students in a poorly performing state school. It is not surprising that various parties are considering legal actions."
He added: "The Royal Statistical Society has claimed that Ofqual has breached its ‘obligation to serve the public good’ and its model failed to ‘achieve quality and trustworthiness’.
"Last week A-levels were allowed to increase by 2 per cent, but for GCSEs this week schools have only been allowed a 1% increase.
"This will result in millions of aggrieved students and many more millions of aggrieved parents and grandparents. If you are in a hole, stop digging.
"The GCSE results should be postponed for two weeks. The Government can then decide either to accept the predicted grades or invite heads to resubmit new predictions which should not exceed 3% of their performance in 2019."
