The present study compared speeches by Iranian President Rouhani, following a moderate political ideology, and his predecessor Ahmadinejad, a seemingly conservative/ principalist president, at the United Nations (UN) General Assembly. The discourse-historical approach was employed to analyze the two corpora. Other discoursal features such as the representation of self and identity were also incorporated into the analysis. The results showed that the two presidents took two different approaches and styles of speech both in the form of delivery and content of their talks. While Rouhani focused on current issues in Iran’s foreign policy, Ahmadinejad made references to the wrong-doings of world powers. Compared with Ahmadinejad, Rouhani followed a more moderate stance in his talk by employing several strategies like keeping use of the pronoun ‘I’ to a minimum and not identifying himself a radical Muslim and savior of mankind. Moreover, the two presidents differed in their employment of premises or ‘topoi’. Findings reveal the role of topoi in uncovering the ideologies of politicians in their public speeches.