Home COVID-19 testing kits have run out, according to a message on the gov.uk website.
The message says: "Sorry, there are no more home tests available right now.
"Try again later.
"Or, you can go back and try to book a test site appointment instead".
The UK Health Security Agency has said that orders of the testing kits sometimes become temporarily unavailable when heavy demand is being experienced.
A UKSHA spokesperson has told people "everyone who needs a lateral flow test can collect test kits – either at their local pharmacy, some community sites and some schools and colleges.
“Due to exceptionally high demand, ordering lateral flow tests on gov.uk has been temporarily suspended to fulfil existing orders".
The note on the website comes less than 24 hours after it was announced that daily testing would become mandatory for those double-jabbed who have come into contact with a positive case.
Those fully vaccinated should take a daily lateral flow test for seven days if they have come into contact with a positive case, in order to slow the spread of the virus.
People who need to take action will be contacted by NHS Test and Trace with further instructions on moves they need to take.
The action comes after a significant rise in Omicron cases across the UK.
Furthermore, the NHS Covid vaccine booking service is "currently facing extremely high demand," meaning a queuing system has been enforced on the website.
Users between the ages 18-29 have been advised that booking opens on Wednesday 15th December.
A Tweet from the official NHS UK Twitter account
People trying to book a COVID-19 vaccine today have been met with technical issues.
Others who have been experiencing waits on the website have been advised to "try again later or tomorrow".
People queuing on the website have been met with a message saying that "lots of people are trying to book an appointment".
The NHS service tells users they can "continue to wait or try again later".
The service had already booked more than 140,000 vaccine appointments on Monday, NHS Digital said, with people waiting several minutes.
Long queues have also been seen outside vaccination sites, as Health Secretary Sajid Javid said the Government will “throw everything at” the Covid booster programme to tackle the Omicron variant.
