Iran on Tuesday described as "unacceptable" upstream dam-building by neighboring Turkey on shared waterways, calling on its neighbor to cease such activity.
"Turkey's construction of dams on the border waters is unacceptable and we oppose it," Iranian Foreign Minister Hossein Amir-Abdollahian was quoted as saying by state news agency IRNA.
He told parliament that the issue had been raised "at least three times these past months during two face-to-face meetings in New York and Tehran and a phone call with the Turkish foreign minister to express our disapproval.
"I asked him to pay particular attention to the construction of dams on the River Aras," he added.
Amir-Abdollahian noted that while "there is no bilateral agreement... on water cooperation, as neighbors, we asked the Turkish government four months ago to form a bilateral committee on water to respond to concerns in this domain".
His remarks come as Iran has faced frequent droughts in recent years, caused in part by climate change, as well as dam-building in neighboring countries.
But alongside Turkey, Iran itself has been responsible for building dams on shared rivers with its neighbor Iraq, threatening access to water there.
Turkey's dam on the Aras has nonetheless posed a particular threat to water availability in Iran.
Neither country is party to the 1997 United Nations Watercourses Convention that regulates the use of transnational water resources.