A level 6 Path of the Totem Warrior barbarian (PHB, p. 50) can choose the Eagle totem, which states:
You gain the eyesight of an eagle. You can see up to 1 mile away with no difficulty, able to discern even fine details as though looking at something no more than 100 feet away from you. Additionally, dim light doesn't impose disadvantage on your Wisdom (Perception) checks.
Combine this with the Observant feat (PHB, p. 168):
If you can see a creature's mouth while it is speaking a language you understand, you can interpret what it's saying by reading its lips.
Using this combination, can I read a creature's lips, speaking a language I understand, from a mile away?