Display screen or portion thereof with graphical user interface

[0001]FIG. 1 is a front view of a first embodiment of the claimed design of a display screen or portion thereof with a graphical user interface; and,

[0002]FIG. 2 is a front view of a second embodiment of the claimed design of a display screen or portion thereof with a graphical user interface.

[0003]The outermost broken lines in the FIGURES illustrate a display screen or portion thereof and form no part of the claimed design. The fluctuating (e.g., wavy) broken line connected to/following the solid line in the charts or graphs in FIGS. 1-2 is a part of the claimed design despite being shown as a series of dashes or broken elements. The other broken lines in the FIGURES illustrate portions of the graphical user interface that form no part of the claimed design.

[0004]The gray filled areas in Figures 1 and 2 represent a contrast in appearance between the gray filled areas and the non-gray filled areas of the claimed designs.