We claim, the ornamental design for a display screen or portion thereof with graphical user interface, as shown and described.
The FIGURE is a front view of a display screen or portion thereof with graphical user interface, showing our new design.
The broken line showing of the display screen is for the purpose of illustrating environment and forms no part of the claimed design. The broken line showing of elements on the display screen illustrate portions of the article and form no part of the claimed design.