Ofqual has said centre-assessed grades should not be used for GCSE and A-level grades in 2021 and that if exams cannot go ahead, a form of online test could be used.

Ofqual chair Roger Taylor, answering questions today from the Commons Education Select Committee, said the regulator had been “very clear that we think that some form of examination or standardised test, or something that gives the student an ability to demonstrate their skills and knowledge, is going to be essential to any awarding system that the students regard as fair”.

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Mr Taylor said Ofqual had consulted on the issue but that this was “obviously a fast-moving environment” and that the future remained “uncertain”, so the regulator was constantly keeping this under review.

A back-up plan for next year’s GCSEs and A levels?

“In terms of a plan B [for 2021] based on centre-assessed grades, our strong view would be not to do that, and we do not think there is a sensible mechanism whereby you can take highly variable evidence from a range of different circumstances and attempt to construct something that is a trustworthy way of discriminating between the students on the base of their knowledge and skills,” he said.

Asked what should happen if exams could not take place, next summer, Mr Taylor added: “There are mechanisms, such as additional papers; there are other mechanisms, including, for example, using online tests.

“We feel we have enough time to come up with a solution to that problem.”

But Geoff Barton, general secretary of the Association of School and College Leaders, said: “While the government plans for a full exam series, we may once again be in a position where at least some students are either unable to take exams or experience significant disruption in their preparation because of the impact of coronavirus and associated restrictions.

“We note with concern Ofqual’s position that this situation can be addressed through additional papers and online tests, and that it has sufficient time to work out a solution.

“This sounds very difficult to manage at any scale, and it would surely be prudent to have a contingency plan in place based on some form of assessment in the autumn and spring term which could be used to reliably inform grades in the event that students are unable to sit exams.

“We are very concerned that there is no such back-up plan, and that time is fast slipping away in which to put such a strategy in place.”

Julie Swan, Ofqual’s executive director of general qualifications, told MPs that some changes had already been made to next year’s exams, for example introducing more choice in GCSE ancient history.

But she said next year’s exams could only be delayed by one or two weeks if they were to meet published results days. And she added that there were concerns over teachers’ “willingness” to mark exams throughout their summer holidays.

She said a decision over next year’s exams format would come within “weeks rather than a period of months”.