GCSE and A-level students will be given grades based on teacher assessments, after exams were cancelled amid the coronavirus pandemic.

The Government said it is aiming for the calculated grades - which will also take into account their previous achievements - to be awarded to pupils in England by the end of July.

Making the announcement on Friday, Education Secretary Gavin Williamson said these are "extraordinary times" and that exam boards would be working closely with teachers to implement the new approach.

Students will also have the option to sit an exam early in the next academic year - which starts in September - if they want to, can appeal if they are not satisfied that their calculated grade reflects their performance, and can choose to sit exams in summer 2021.

The new guidance states that exam boards will be asking teachers to submit judgments about the grades they think their students would have received if exams had gone ahead.

Teachers will have to take into account "a range of evidence and data", such as mock exam results and other school work, the department said.

This will be combined with information from "other relevant data", such as pupils' previous attainment, to calculate their grades.

The calculated grades will be "a best assessment" of the work students have put in, the Government said.

A-level and GCSE grades are usually published in mid-August.

Mr Williamson said: "Cancelling exams is something no Education Secretary would ever want to do, however these are extraordinary times and this measure is a vital but unprecedented step in the country's efforts to stop the spread of coronavirus.

"My priority now is to ensure no young person faces a barrier when it comes to moving onto the next stage of their lives - whether that's further or higher education, an apprenticeship or a job.

"I have asked exam boards to work closely with the teachers who know their pupils best to ensure their hard work and dedication is rewarded and fairly recognised."

The department said this year's grades will be "indistinguishable from those provided in other years" and would aim to ensure that the distribution of grades follows a similar pattern to previous years, so affected students do not face a "systematic disadvantage".

It also outlined various options for students and parents who may not be happy with the approach or their calculated grades.

The department said: "If they do not believe the correct process has been followed in their case they will be able to appeal on that basis.

"In addition, if they do not feel their calculated grade reflects their performance, they will have the opportunity to sit an exam at the earliest reasonable opportunity, once schools are open again.

"Students will also have the option to sit their exams in summer 2021."