He said he now has other dreams he would like to pursue.
The 56-year-old made the announcement on social media on Thursday morning saying he had a "bit of a change about to happen in his life".
In a statement he said: "Anchoring my own breakfast show for 11 years has been for me the stuff of boyhood dreams. It was the job I hoped to do as a young Belfast lad - and because of Sky News I got there!
"Forty five years plus on I have other dreams, and to achieve them I realise that unfortunately I need to step away from the daily studio commitment for a while. There is an addiction to a live breaking news studio environment. However, after more than 3,000 hours of programming it is a habit I have to suppress. Increasingly in life I have found myself in the fortunate position of having so much to do but little time to do it. This seems an opportune moment to change that.
"Going forward, I will now produce and present a number of documentary projects which I have been stalling for some time, as well as continuing my work with ITV and Channel 5. There is so much going on and I realised it was now or never...
"Sky's Head of News, John Ryley, has been very understanding and sympathetic of my decision. I would like to publicly thank him and the wider Sky family for all their support throughout my time at Osterley. John’s counsel and guidance in helping me to reach this decision has been invaluable.
"Finally, I cannot stress how hard it is saying goodbye to such a programme and the friends and colleagues who I have met over the years because of it - but nothing stays the same - nor should it. New studios mean a wonderful chance for new ideas and a new approach with new presenters.
"I hope they enjoy and respect the privilege of hosting Sunrise and waking up Britain and the world as much as I have. To those who have worked or woken up with me on Sky News over the years - thank you. I hope you appreciated that I tried to do it differently."