Display Screen or Portion Thereof with an Animated Graphical User Interface

FIG. 1 is a front view of a first image for a display screen or portion thereof with an animated graphical user interface showing our new design;

FIG. 2 is the second image thereof;

FIG. 3 is the third image thereof;

FIG. 4 is the fourth image thereof; and,

FIG. 5 is the fifth image thereof.

The appearance of the animated graphical user interface sequentially transitions between the images shown in FIGS. 1 to 5 . The process or period in which one image transitions to another forms no part of the claimed design. In the FIGS., the outermost broken lines show a display screen or portion thereof and form no part of the claimed design. The remaining broken lines show elements of the animated graphical user interface that form no part of the claimed design.