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 lines illustrating portions of the display screen or portion thereof with graphical user interface are for environmental purposes only and form no part of the claimed design. In addition, any other broken lines such as but not limited to those showing the alphanumeric characters and symbols are for environmental purposes only and form no part of the claimed design.