It is “not appropriate” for schools to send whole year groups to be tested for Covid-19, the health secretary has said.

Matt Hancock said that people “shouldn’t be coming forward” for tests if they do not have symptoms, or have not been asked to get tested “specifically by a clinician or by a local authority”.

The news comes as the government has been warned its Covid-19 testing has descended into “an absolute shambles” that has left people facing 700-mile round trips.

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Teachers have also complained that the current system is “not fit for purpose” after several reported that they missed classes because of a lack of available tests.

Speaking to Sky News, the health secretary said there had been an increase in people seeking tests without symptoms of Covid-19.

And there have been stories of schools sending a whole year group for tests, which is “not appropriate”, he added.

“At the moment, the system is really very straightforward because we wanted it to be easy for people with symptoms to get a test,” he said.

“But the message is also clear that if you’re not eligible for a test - if you don’t have symptoms or you haven’t been asked to get a test, specifically by a clinician or by a local authority - then you shouldn’t be coming forward to get a test, because it makes it harder for people who really need them to get those tests.

“We’ve had stories of schools sending a whole year group to go and get a test, and that is not appropriate. What is appropriate is if you have symptoms and get a test.”

The free tests are available to people with symptoms of coronavirus - a fever, a new and continuous cough, or a loss or change in sense of taste or smell - and for some others such as those who have been instructed to do so by a doctor or local council and some essential workers.