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 view of a display screen or portion thereof with graphical user interface.
The broken lines in the figures show portions of the display screen or portion thereof with graphical user interface which form no part of the claimed design. The dot-dash lines in the figures represent an unclaimed boundary line and form no part of the claimed design.