In his message released late on Tuesday, President Rouhani felicitated the Iranian nation on the Islamic festival of Eid al-Fitr, which marks the end of the holy month of Ramadan.
He also expressed the hope that Muslims would resort to the illuminating teachings of Islam to strengthen unity and solidarity on the basis of moral values, moderation and rationality.
The president also expressed confidence that national unity and rapport in Iran will help the country make greater strides in the national and international arenas.
Eid al-Fitr, also called Feast of Breaking the Fast, is an important religious holiday celebrated by Muslims around the world.
On the Eid day, which has fallen on Wednesday in Iran and many other Islamic countries, Muslims attend prayers in congregation, listen to sermons and give Zakat al-Fitr or donations to the poor.