According to ISNA, President's message is as follows:
In the Name of Allah, the Most Beneficent, the Most Merciful
Your Excellency Mr Moon Jae-in,
President-elect of South Korea,
I sincerely congratulate your election as the President of South Korea.
I hope in your term of office, relations between the two countries of the Islamic Republic of Iran and the Republic of Korea be further developed.
I pray to the Almighty for your Excellency's health and success, as well as the South Korean nation's felicity and prosperity.
Hassan Rouhani
President of the Islamic Republic of Iran