Azerbaijan has summoned Iran's interim chargé d'affaires to the Foreign Ministry, demanding an end to what it called "provocative actions" by Tehran, according to a report by Tasnim news agency on Wednesday.
The move follows a live broadcast on Iran's state news channel featuring inflammatory and insulting rhetoric during a religious ceremony.
The remarks targeted Turkish President Recep Tayyip Erdoğan and Azerbaijani President Ilham Aliyev.
A religious singer at a ceremony compared current Iran-Turkey-Azerbaijan tensions to a 16th-century Ottoman-Safavid war. He insulted Presidents Erdoğan and Aliyev and said that Iran would reclaim territories in Azerbaijan, invoking religious symbolism.
The territory of what is now called the Republic of Azerbaijan was separated from Iran in the first half of the 19th century, through the so-called Russo-Persian Wars.
The event took place in the presence of a representative of Iran’s Supreme Leader Ali Khamenei in the northwestern city of Ardabil earlier this week.