Secondary school pupils in England will not be required to wear masks when they return to class despite their Scottish counterparts potentially being ordered to don face coverings.

Education Secretary Gavin Williamson said measures being adopted by schools to limit the spread of coronavirus meant masks were not required.

But in Scotland, the Government is consulting on measures which could see masks worn by secondary school pupils and teachers in corridors and other communal areas, although not in classrooms.

The World Health Organisation and UN children’s agency Unicef advise that adults and children aged 12 and over should wear a mask, particularly when they cannot guarantee at least a one-metre distance from others and there is widespread transmission in the area.

But Mr Williamson insisted there was no need to do so as senior Government figures – including Prime Minister Boris Johnson – pleaded with parents to send their children back to England’s schools in September.

The Education Secretary said the Government was not suggesting the wearing of masks because “we believe there is a system of controls there in place in all schools for children to be able to return safely and for staff to be able to operate safely”.

England’s deputy chief medical officer Jenny Harries said the evidence on whether children over 12 should wear masks in schools was “not strong”.

Dr Harries told Sky News that in children under 15 “compliance is very poor” and other measures being taken in schools – such as children sitting side by side or back to back meant masks were not needed.

“We also need to think through the sort of psychosocial effects of masks for children, it’s a learning environment, and we need them to learn for life,” she added.

A Number 10 spokesman said: “There are no plans to review the guidance on face coverings in schools.

“We are conscious of the fact that it would obstruct communication between teachers and pupils.”

The WHO and Unicef suggested that face shields may be an alternative in situations such as speech classes where the teacher and pupils need to see each other’s mouths.

Shadow education secretary Kate Green said the issue should be kept under review.

Scotland’s First Minister Nicola Sturgeon said her Education Secretary John Swinney is in the final stages of consulting with teachers and councils on whether to recommend the use of masks when moving around schools.

The move follows requests from some schools north of the border for pupils to wear face coverings.

Ms Sturgeon said: “Mixing between different groups is more likely in corridors and communal areas – increasing the potential for transmission.

“Secondly, crowding and close contact in these areas is more likely and voices could be raised, resulting in greater potential for creating aerosol transmission.

“Finally, there’s also less scope for ventilation in these areas.”

The potential split between England and Scotland over mask-wearing comes as the Westminster Government sought to reassure anxious parents about the safety of schools.

Ministers stressed that it would be compulsory for pupils to attend classes, with the risk of fines for parents who did not comply – although Mr Williamson said they would only be used as a last resort.

Local authorities can fine parents £120 – cut to £60 if paid within 21 days – over a child’s absence from school, with the threat of prosecution if they fail to pay.

Mr Williamson said: “In terms of fining, we would ask all schools to work with those parents, encourage them to bring their children back, deal with concerns that they have and fining would be very much the last resort, as it has always been.”

The Prime Minister acknowledged that parents “are genuinely still a bit worried” about their children contracting coronavirus.

“All I can say is the risks are very, very, very small that they’ll even get it, but then the risk that they’ll suffer from it badly are very, very, very, very small indeed,” he said.

“I think it’s vital that parents understand that schools are safe and that teachers have gone to great lengths to get schools ready.”

The Government has repeatedly said that schools will be the last thing to shut if there are local lockdowns and if that happened, Downing Street said teachers would be expected to continue classes remotely.

In other developments:

– Schools began the process of reopening in Northern Ireland.

– The NHS Test and Trace system has faced fresh criticism for a flaw in its online booking system which tries to direct people to test centres more than 100 miles away.

– The first case of someone being reinfected with coronavirus has been reported by researchers in Hong Kong.

The task of getting children to return to classrooms comes with Mr Johnson and Mr Williamson under pressure following the fiasco over A-level grades.

Downing Street said the Prime Minister is “sorry for any distress” caused by the way grades were awarded after the cancellation of GCSE and A-level exams – initially using an algorithm but then, following a U-turn, based on teachers’ assessments.