Fines for parents who refuse to send their children to England’s schools will only be used as a “last resort” as classes resume after the coronavirus shutdown.

School Standards Minister Nick Gibb said there was a “moral imperative” for children to attend classes when they return next month.

Preparations for the return of England’s schools come with Education Secretary Gavin Williamson under intense pressure following the fiasco over the awarding of A-level grades.

Prime Minister Boris Johnson has led calls for parents to send their children back to class and the UK’s chief medical officers have said youngsters are more at risk of long-term harm if they do not attend school than if they return.

Mr Gibb acknowledged that some parents would still have concerns but stressed that education was compulsory and fines could be used if necessary.

“Fines for non-attendance have always been a last resort for headteachers and schools,” he told BBC Radio 4’s Today.

“What matters is that young people are attending school.

“We live in a country where education is compulsory and I think parents can be reassured that the measures that schools are taking to make sure that we minimise the risk of the transmission of the virus are very effective.”

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 Gibb said if parents had concerns they should be able to discuss them with headteachers.

“But it is important – it’s a moral imperative – that young people are back in school, because what the chief medical officers are saying now is that the risk of not being in school outweigh the very small risk of children being in school, particularly given all the control measures, the hygiene, the cleaning that’s taking place in our schools … there’s an absolute determination to make sure that schools are safe for the children and children want to be back.”

Shadow education secretary Kate Green accused the Government of going “missing in action” and being “asleep at the wheel”.

She told ITV’s Good Morning Britain: “The guidance that’s been given to schools is one-size-fits-all, it doesn’t take account of the fact that a small school, perhaps in very constrained premises will have to make different arrangements from a large inner city school.

“There hasn’t been information for school leaders, so that they can’t plan what they might have to do if there was a sudden spike in the local infection rate and the guidance that has come out I think has been – it’s been contradictory, it’s been confusing, it came very late, shortly before the summer holidays.”

Many pupils in England have not been to class since March, when schools were closed except to look after vulnerable children and those of keyworkers.

Schools in Scotland reopened earlier this month, while those in Northern Ireland were welcoming pupils again on Monday.

English and Welsh schools will follow suit in September.

The Prime Minister said: “It’s vitally important that we get our children back into the classroom to learn and to be with their friends.

“Nothing will have a greater effect on the life chances of our children than returning to school.”

Former Conservative leader Sir Iain Duncan Smith wrote in the Daily Telegraph that the Government “needs to show it governs with a steady hand, based on a clear strategy and message”.

He added: “This battle over schools reopening must see the Prime Minister in the lead, galvanising his inner Churchill.”

A Public Health England (PHE) analysis, published on Sunday, found there were 67 single confirmed cases, four “co-primary cases” (two or more linked cases diagnosed at the same time) and 30 outbreaks of Covid-19 in schools during June.

It said the majority of cases linked to outbreaks were in staff and warned that school staff needed to be “more vigilant for exposure outside the school setting to protect themselves, their families and the educational setting”.

The analysis also said further school closures may be necessary in regions with increasing community infection but this should “be considered only in extremis”.

England’s deputy chief medical officer Jenny Harries told Sky News: “No environment is completely risk-free. Every time a parent sent their child off to school pre-Covid they may have been involved in a road traffic accident, there are all sorts of things, and in fact that risk – or the risk from seasonal flu – we think is probably higher than the current risks from Covid.”

Education unions have called for greater clarity on how schools should handle a spike in coronavirus cases.

Kevin Courtney, joint general secretary of the National Education Union, said: “Government advice needs to cover the possible self-isolation of bubbles and, in extremis, moving to rotas or to more limited opening.

“It needs to cover advice to heads about the protections needed for staff in high-risk categories if infection rates rise.”

Liberal Democrat education spokeswoman Layla Moran called on Mr Johnson to sack Mr Williamson to “restore confidence among parents, pupils and teachers”.

On Sunday, the Education Secretary defended a trip to see “family in Scarborough” after reports he visited the Yorkshire seaside resort for a holiday the week before the A-level results fiasco.

Mr Williamson wrote on Twitter: “I cancelled our family holiday abroad this year to focus on the challenges Covid-19 created for the education sector.

“Over the summer, I went to see family in Scarborough for the first time since lockdown, and while there I was in constant communication with the Department.”