Teaching unions have attacked “ignorant” Gavin Williamson after he announced last-minute changes to the way A-level and GCSE results will be dealt with.

Education secretary Williamson said late on Tuesday that students in England will be able to use their results in mock tests to appeal if they are unhappy with the expected grades they are given by teachers, and which are then moderated by exam boards.

The move came less than 48 hours before students receive predicted A-level results following the cancellation of actual exams amid the COVID-19 crisis.

Responding to Williamson’s “embarrassing U-turn”, Dr Mary Bousted, joint general secretary of the National Education Union, said on Wednesday: “He should have listened to the concerns raised much earlier by teachers and assessment experts.

“He should have worked with the profession to establish a sound basis for grades which can determine pupils’ life chances.

“Ignorance and inaction appear to have been his watchwords.”

As well as being able to appeal using mock exam results if they are unhappy with their expected grades, students will also be given the option to sit their exams in the autumn.

All outcomes will hold the same value for universities, colleges and employers, with Williamson saying it will “ensure [students] are able to progress with the next stage of their lives”.

However, Dr Bousted said the two alternatives to the expected grades remain insufficient.

Mock exams, she said, “do not take into account expected further progress” as they are taken much earlier in the academic year.

Meanwhile, she added, Williamson has not answered questions about how exams could be taken in “COVID-secure schools” in the autumn.

Geoff Barton, general secretary of the Association of School and College Leaders, also said the U-turn “beggars belief”.

He said: “Schools and colleges have spent months diligently following detailed guidance to produce centre-assessed grades, only to find they might as well not have bothered.”

However, school standards minister Nick Gibb told BBC Breakfast on Wednesday: “We apologise to nobody for finding solutions, even at the 11th hour, to stop any student being disadvantaged by this system.”

The government’s decision came in the wake of a separate U-turn by the Scottish government.

Scotland’s education secretary John Swinney announced that moderated grades would be scrapped following a massive outcry after more than 124,000 results were downgraded.

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