A siren-like warning alert will be sent to mobile phones and tablets across the UK on 23 April as part of a test for a new government warning system designed to alert the public to life-threatening situations.

The test – which has been confirmed to be set for 3pm on Sunday 23 April – will see a message pop up on home screens, accompanied by vibrations and a warning sound that will play for about 10 seconds.

The sound will play even if the phone is set to silent, and users will have to acknowledge the alert by clicking ‘OK’ before they can continue using their device.

Originally the plan for the test was for later on in the evening, but the time was shifted to avoid clashing with a football final, which kicks off at 4.30pm. The afternoon time was also chosen to avoid the start of the London Marathon, which begins at 9.30am on the same day.

The system has been modelled on similar schemes already operational in the US, Canada, Japan and The Netherlands, and it’s hoped the warnings will help the government and emergency services prepare the public for serious weather events, such as flash floods or wildfires.

A new government warning system will be tested on phones in April – here’s what to expect