Anyone enjoying a Sunday afternoon slumber on 7 September is set to be woken by the latest national test of the UK's emergency alert system.
Millions of Brits' phones will vibrate and make a siren sound for around 10 seconds as they receive a text of fewer than 100 words at around 3pm on the day.
It will assure the public that they 'do not need to take any action' and include a message in both English and Welsh.
The Government has been carrying out a public awareness campaign to ensure people know when the test is taking place, including those facing domestic abuse who may have hidden phones.
The Cabinet Office said the text message will be sent to mobile phones on 4G and 5G networks in the UK.
