I have a picture of my uncle, then commander Hans B. Gundersen in galla uniform (mess dress) and my aunt Inger walking up those stairs - in 1957. The occation was that, back then, Paris was the seat of the NATO headquarters. My uncle was norwegian navy attache in Paris. They are both dead, but I still have the photograph of them. Somewhere.
The picture taken of them is about where you see people coming up the stairs. (Elysee Palace? Or the Paris Opera?)
The photographer must have stood much farther down the stairs to take pictures of - possibly, each and every of the guests arriving at the occation. The background, the guards etc. are very familiar.