Love the wallpaper. What room is it for? If a bedroom, how about a pale duck egg blue? Agree with PP that a dove grey would look lovely too. I wouldn't personally go for the background colour as it would make the room look too harsh/sterile with white walls.
I thought that too about the background colour. It is for a bedroom but it's a large room and I wonder if the blue would just make it all too blue although that was my first thought. How about a natural stone kind of colour?