Display screen or portion thereof with an animated graphical user interface

[0001]FIG. 1 is a front view of a first image of a display screen or portion thereof with an animated graphical user interface; and,

[0002]FIG. 2 is a front view of a second image of a display screen or portion thereof with an animated graphical user interface.

[0003]The broken lines shown in the drawing illustrate portions of the display screen or a portion thereof with a graphical user interface that form no part of the claimed design. The appearance of the display screen or portion thereof with animated user interface transitions sequentially between the views shown in FIGS. 1 and 2, respectively. The process or period in which one FIGURE transitions to another forms no part of the claimed design.