The prime minister has said "exams" will be "fair" and "properly adjusted" to reflect the disruption of the past 12 months.
Boris Johnson's comments today come despite his government's cancellation of this year's GCSE and A-level exams and the fact that it had not been planned for teacher-assessed grades to be adjusted to reflect students' differing levels of Covid disruption.
Earlier this month, Ofqual chief regulator Simon Lebus said: "The issue of how you address lost learning is not an issue for exams."
But questioned tonight on how the government would ensure that "no child is left behind", Mr Johnson said the government would tackle differential lost learning "across the country" by making sure that exams are "adjusted".
GCSEs 2021: Four reasons why more unfairness is inevitable
The question from a member of the public at today's Downing Street coronavirus briefing asked: "With the government expected to extend school closures until Easter, what strategy will the government publish to ensure no child is left behind?"
GCSEs and A levels 2021: 'Exams will be properly adjusted'
The prime minister responded: "What we will do...is work around the clock as we come out of lockdown to ensure that kids who have suffered, pupils who have suffered from loss of learning, from differential learning across the country, get the attention, get the tuition and support that they need.
"And we'll make sure that exams are fair and properly adjusted to reflect what everybody has been going through in the last 12 months."
There have been concerns that GCSE and A-level results this year would not be fair for all because grades would not be adjusted to account for different levels of Covid disruption.