Education Secretary Gavin Williamson said there would be “no algorithms whatsoever” used in determining grades for students this summer.
The minister said there would be a “clear and robust” appeals mechanism for A-level and GCSE students who are unhappy with their results.
His comments came just hours before the Government was due to set out the detail on how grades will be calculated in England after exams were cancelled.
When asked about assessment, Mr Williamson told a Downing Street press briefing: “As I said many times before, we are putting trust in teachers.
“That’s where the trust is going, there is going to be no algorithms whatsoever but there will be a very clear and robust appeals mechanism.”
Thousands of A-level students had their results downgraded from school estimates by a controversial algorithm before Ofqual announced a U-turn which allowed them to use teachers’ predictions.
On Wednesday, ministers announced an additional £400 million of funding to help pupils in England catch up from coronavirus disruption.
Secondary schools have been asked to deliver some summer teaching as part of the package to help counteract the months of classroom closures.
The Education Secretary told a press briefing that lengthening the school day was not part of the Government’s immediate plans to recover lost learning.
But Mr Williamson added: “What we are wanting to do is see a real change, a step change, in what we can deliver in terms of our schools.
“That’s why we are taking this in-depth look at how do we drive results, how do we drive attainment, how do we drive the chances of youngsters from the most disadvantaged backgrounds.
“That’s why we have asked Sir Kevan to do this extensive look at education and what reforms, what changes we can bring about.”
Sir Kevan will develop longer term plans for how evidence-based interventions can be used to address the impact of Covid-19 on learning after engaging with schools, colleges, charities and parents.
Mr Williamson said: “Despite everyone’s best efforts, many children are going to need longer term support if they’re to make the educational progress that they need.”
This week, the Government announced that secondary school and college students in England will be asked to take regular coronavirus tests at home when they return to school next month.
The Prime Minister confirmed that all pupils will return to class from March 8, but the return of students in secondary schools and colleges could be staggered due to the logistics of mass testing.
Addressing the press conference on Wednesday, Mr Williamson said he hoped that parents would support children to carry out twice weekly testing at home.
He added that everything was “strongly in favour” of children returning to classrooms on March 8.