We claim the ornamental design for a display screen or portion thereof with graphical user interface, as shown and described.
FIG. 1 is a front view of a display screen or portion thereof with graphical user interface showing our new design; and,
FIG. 2 is a front view of a display screen or portion thereof with graphical user interface, on an enlarged scale, the graphical user interface is shown separately from the display screen.
The broken line showing of a display screen or portion thereof forms no part of the claimed design.