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 an enlarged front view of the graphical user interface, shown separately for completeness of illustration.
The evenly spaced broken lines illustrate a display screen and electronic device as the environment of a display screen or portion thereof with graphical user interface and form no part of the claimed design. It should be appreciated that at least a portion of the display screen is shown inside the broken lines. The dot dash lines define the boundary of the claimed design and form no part thereof.