"I express my sincere congratulations to the people of Sri Lanka on the recent successful presidential election and also to the President, Anura Kumara Dissanayake, on his victory in the election," the Iranian Foreign Minister Abbas Araghchi wrote on his X account.
"We are confident that the good and friendly relations between the two nations of the Islamic Republic of Iran and Sri Lanka will continue and improve under his leadership," the Iranian top diplomat added.
Sri Lanka's new president Anura Kumara Dissanayake has been sworn into office, promising "clean" politics as the country recovers from its worst economic crisis.
The left-leaning Dissanayake has cast himself as a disruptor of the status quo, and analysts see his victory as a rejection of corruption and cronyism that has long plagued the country.
Saturday's election was the first since 2022, when discontent over the economy fuelled mass protests and chased former president Gotabaya Rajapaksa from power.
MNA/IRN85605665