The singer-songwriter and producer has penned hits for the likes of Beyonce and Leona Lewis, but says nothing has affected him as much as hearing the results of his studio session with Adele, her moving ballad 'Turning Tables'.
Ryan told the new issue of Notion magazine: ''It's easy to look back at your most successful singles and call them your favourites, but I knew there was something special when we came up with 'Turning Tables'.
''After we worked on the song I went back to my hotel room in London and I texted her saying, 'I'm listening to your demo and I'm getting choked up.' She said, 'I've been crying my eyes out for the last 20 minutes.'
''We both thought we'd nailed it. It doesn't matter that it wasn't a radio hit. In a perfect world, the two would coincide. Most artists would be lying if they didn't say that was the goal.''
Ryan explained: ''For three years mine and Florence Welch's managers have been trying to get our calendars to align. We're always on the opposite sides of the world.
''I really want to do something with her - I think we can crack something that she hasn't done and that I haven't done. I really think it could be huge.''
OneRepublic's new single 'Love Runs Out' is available for iTunes pre-order, released on July 27.