Display screen or portion thereof with an animated graphical user interface

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

FIG. 2 is a front view of a second image thereof;

FIG. 3 is a front view of a third image thereof;

FIG. 4 is a front view of a fourth image thereof;

FIG. 5 is a front view of a fifth image thereof;

FIG. 6 is a front view of a sixth image thereof;

FIG. 7 is a front view of a seventh image thereof; and,

FIG. 8 is a front view of an eighth image thereof.

The appearance of the transitional image sequentially transitions between images shown in FIGS. 1 through 8 . The process or period in which one image transitions to another image forms no part of the claimed design.

The broken lines illustrating the display screen and portions of the animated graphical user interface illustrate portions of the display screen or portions thereof with an animated graphical user interface which form no part of the claimed design.