Abstract. The peace agreement signed between Armenia and Azerbaijan in August 2025 in Washington is not only an important step in advancing the peace process in the South Caucasus, but also a new balance of power in the region. Interested countries such as Russia and Iran are closely monitoring the events in the South Caucasus, expressing both satisfaction with the progress of the peace process and concern about the emergence of a new major player in the region: the United States. The transformation of the peace agreement into a full-fledged peace treaty is currently facing difficulties caused by Azerbaijan's new demands on Armenia and Armenia's reluctance to recognize them. Azerbaijan, Armenia, the United States, Russia, Iran, and the peace agreement.