The Canadian singer will no longer be at the ceremony on 22 February as he continues to dedicate all of his time to his three-year-old son Noah, who is undergoing treatment for cancer.
The new hosts said they were delighted to be at the helm of the UK’s biggest music awards bash, but added that their thoughts are with Michael.
Dermot said: “Firstly, my immediate thoughts and prayers are with Michael and his family at such a difficult time.
“Michael is an effortless show man, so those patent shoes will not be easy to fill, but it’s an honour to be asked to step in with Emma to host the BRITs.
“The BRITs is an iconic show that I’ve watched and attended many times. It’s a holy grail for a broadcaster, and I’m really looking forward to working with Emma, who I’m a big fan of, and celebrating a brilliant year of British music.”
Emma added that her thoughts were also with Michael at this difficult time.
“Every part of me sends so much love and all the well wishes in the world to Michael and his family at such a difficult time,” she said.
“I’m a huge fan of his and I would have relished watching him present the BRITs. I know everyone involved wants to make the best show possible and I hope we do him proud.
“To present the BRITs is an honour but to be doing it alongside one of my absolute favourites, Mr Dermot O’Leary, is just bonkers. Bring on The BRITs 2017!
Brits chairman Jason Iley said he was hugely excited about securing Dermot and Emma to present the awards.
“They are currently the most in demand presenters in the UK, with a huge passion for music, and to get the both of them is very exciting for us,” he said.
“Our thoughts go out to Michael and his family. We would love to see him on our stage in the future.”
The Brit Awards will be held at London’s O2 Arena on 22 February.