The United Kingdom's Education Secretary has announced that all schools have been closed until further notice starting Friday.

After UK schools close on Friday afternoon, they will remain closed for most students, Prime Minister Boris Johnson said in his daily coronavirus news conference Wednesday.

The students who will be allowed to go to school will be the children of key workers, whose parents still need to go to work.

“For many parents these steps will be frustrating… that’s why we are now working on further measures… to keep our economy going,” Johnson said.

He warned children should not be left with older relatives who may fall into the vulnerable groups.