Matt Hancock has stressed to parents that schools are for key workers' children only during the third national lockdown.
It comes after rows erupted over parents 'needlessly' taking up key worker spaces in schools.
The Manchester Evening News reported earlier this week how some key workers said they'd been refused places for their children, despite working in schools and for the NHS.
Education secretary Gavin Williamson also said earlier this week that kids who didn't have access to digital devices are allowed to come in to learn in classrooms - alongside the children of key workers.
This lead to schools reporting increased demands for places for students in schools and colleges despite being told to learn remotely until mid-February unless they fall into the key worker or vulnerable group.
But Mr Hancock warned on Sunday (January 10) while speaking to Sky News: "It's always been the guidance that schools are there for key workers' children where key workers need to have the children in school in order to be able to get to work."
The Health Secertary added: "For instance, if you’re a key worker and your partner doesn't work then you shouldn't be sending your children to school. That’s clear in the guidance. But of course the reason that we keep schools open for key workers' children is that this is important.
"It is important – for instance – that key workers in the NHS but not just the NHS – can get to work and so it’s a very difficult balance to strike.
"I understand that more people are sending their children to school than they did last time. But we really do need everybody who works in the NHS where at all possible to be able to make it to work."
The Department for Education (DfE) said in fresh guidance on Thursday that children with at least one parent or carer who was a critical worker could attend class – even if parents were working from home.
According to government guidance schools in England should not limit the number of children of key workers onsite during the national lockdown.
You can see the full list of critical workers and vulnerable children here.
