A siren-like emergency warning message will be sent by the Government to mobile phone users across the UK next month to test a new public alert system.

Phone users will be unable to use other features on their devices unless they acknowledge the alert, due to be sent on Sunday April 23.

The system – modelled after similar schemes in the US, Canada, the Netherlands and Japan – is intended to be used in life-threatening situations including flooding and wildfires.

The alerts will appear on the home screens of people’s phones, accompanied by a loud warning sound and vibration.

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The scheme will initially focus on the most serious severe weather-related events, with the ability to get a message to 90% of mobile users within the relevant area in an emergency.

Chancellor of the Duchy of Lancaster Oliver Dowden said: “We are strengthening our national resilience with a new emergency alerts system, to deal with a wide range of threats – from flooding to wildfires.

“It will revolutionise our ability to warn and inform people who are in immediate danger, and help us keep people safe.

“As we’ve seen in the US and elsewhere, the buzz of a phone can save a life.”

People who do not wish to receive the alerts will be able to opt out in their device settings, but officials hope the life-saving potential of the messages means that users will keep them on.

The alerts will only ever come from the Government or emergency services, and they will include the details of the area affected, and provide instructions about how best to respond.

The Cabinet Office said the alerts are secure, free to receive, and one-way, insisting they do not reveal anyone’s location or collect personal data.

Tests of the service have already taken place in East Suffolk and Reading.

The scheme could eventually be expanded to cover terrorist incidents, but officials acknowledged that much more information about how the alerts system operates in the UK would be needed before that could happen in response to a fast-moving attack.