Parents should make sure their children are tested regularly for the coronavirus, education secretary Gavin Williamson said, as he warned pupils not to get “carried away” when schools return.

The government is trying to persuade parents, secondary school pupils and college students to take part in voluntary asymptomatic Covid-19 testing amid concerns that the return to classes in England in September could drive a new wave of infections.

Mr Williamson said the easing of restrictions and the return of schooling, which is “closer to normality”, is welcome but warned that parents and children should not “throw caution to the wind”.

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Writing in the Daily Mail, he said: “At long last, we will see children once more free to chase a football around, sing in a choir or just hang out with friends. I am absolutely delighted.

“After all, children and their parents have had to put up with so much disruption over the past 18 months.

“It is important not to get too carried away with these new freedoms and throw caution to the wind. The fact that we are in the happy position we are now in is because everyone has worked hard to follow the national guidelines. We still need to do so.”

Schools will still need to follow Covid precautions, with regular testing a key element, Mr Williamson said.

“Parents, too, have a responsibility to make sure that their children are tested regularly. I know that there are many things people would rather be doing than testing but it’s really important to make time for it,” he said.

“The last thing we want is for schools to partially close again or for whole classes of pupils to be at home self-isolating.”

Mr Williamson also suggested that schools should consider keeping lunch bubbles to improve pupil behaviour this term.

He told the Mail: “It brings so many benefits - not just to children but to the whole ethos of the school.

“Not all children will have that regular experience of being sat around a family dinner table. I think it’s an important part of their personal development and it supports... their educational development as well.”

Department for Education guidance states that secondary school and college students in England should be tested twice on site on their return, with lateral flow tests carried out between three and five days apart.

Pupils should then continue to test twice weekly at home until the end of September, when the policy will be reviewed.

Mr Williamson’s comments came just days after experts warned that it is “highly likely” there will be large levels of coronavirus infection in schools by the end of September.

Advisers have told the government to plan for this outcome, as it will be uncertain whether the high prevalence might be a result of spread of the virus within schools or in the community.

And teachers’ leaders have warned that schools will need to reintroduce Covid safety measures as pupils return to the classroom.

Yesterday evening, Mary Bousted, joint general secretary of the NEU teachers’ union, told The Telegraph: “We have much higher prevalence now in the community than it was. So we’re going in with much higher rates of prevalence into schools where we are relying on one mitigation, which is lateral flow testing.

“In Scotland, they have not abandoned the safety precautions...they have still maintained social distancing where possible; they are still, in secondary schools, using masks.

“My prediction is that, very shortly, we are going to see schools all over the country in their hundreds having to operate contingency frameworks. But what you’re doing there is shutting the stable door after the Covid horse has bolted.”

In a document from the Scientific Pandemic Influenza Group on Modelling operational sub-group, experts said the Covid vaccine rollout - which currently extends only to 16-year-olds and above - will have made “almost no difference” to many pupils.