Dec interrupted last night's episode (05.10.19), asking viewers to forget about the acts for a moment, as the campaign was explained.
"In the past 15 years there has been a staggering 48% rise in depression and anxiety amongst British children," he said.
"But something as simple as talking together and listening to each other can build our mental wellness."
Ant, who has been open about his own mental health issues, added: "We all know that these days there are more distractions than ever as we're looking at the telly or at our phones.
"But it's so important for our mental well-being to get together with people we care about and talk."
Something as simple as talking together and listening to each other can build our mental wellness.
The studio then fell silent for a minute, as Dec invited viewers at home to talk to each other.
The project, Britain Get Talking, is being supported by a host of TV stars including Dermot O'Leary, Holly Willoughby, Phillip Schofield, Amanda Holden, Gordon Ramsay, Gino D'Acampo, Jonathan Ross and Myleene Klass.
It is also backed by mental health charities Mind and YoungMinds, and SAMH in Scotland.
The five-year programme aims to improve the mental or physical health of some 10 million people.
The incentive was roundly applauded by viewers on Twitter.
One fan posted: "Big respect to BGT for 'pausing' their show to encourage people to talk about mental health."
"Ant and Dec talking about mental health awareness actually made me really really emotional. I love you guys so much. As a sufferer of anxiety and depression, this meant the world to me," wrote another.
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