Iranian President Hassan Rouhani in separate messages to Indian president and prime minister expressed congratulations on the Republic Day of India.
In his messages to Ram Nath Kovind and Narendra Modi, Rouhani wished for developing cooperation between Tehran and New Delhi in all fields based on potentials.
He recalled the cultural and historical commonalities between two countries and hoped for enhanced relations.
Iran and India have so far passed the golden era of bilateral relations, Rouhani said.
Republic Day honors the date on which the Constitution of India came into force on January 26, 1950 replacing the Government of India Act as the governing document of India.
The Constitution was adopted by the Indian Constituent Assembly on 26 November 1949, and came into force on 26 January 1950 with a democratic government system, completing the country's transition towards becoming an independent republic.
The 26 January was chosen as the Republic day because it was on this day in 1929 when the Declaration of Indian Independence (Purna Swaraj) was proclaimed by the Indian National Congress as opposed to the Dominion status offered by the UK.