Other pacts included one on "Exchange of Instrument of Ratification of Extradition Treaty" that "brings into effect the Extradition Treaty signed between India and Iran in 2008', and others in the fields of health, medicine and agriculture".
During the talks between the two leaders, India is also believed to have briefed Iran about the role of Pakistan-sponsored terrorism in attempts to destabilise the situation in Kashmir.
Underlining that Iran can supply India's need for energy under long-term agreements, Rouhani said that "such long-term agreements on fields of energy and transportation will make the two countries safe partners".
Iran, which used to be the second-biggest oil supplier to India before sanctions, is gradually raising its market share in the world's third-biggest oil consuming nation.More news: Arnold Schwarzenegger Cast in Kung Fury Movie
Rouhani stressed that "Iran and India's ties are not to any country's detriment".
Rouhani referred to Trump's threat on the nuclear deal, and said that "politics without adhering to one's commitment and promises can not resolve the conflicts and problems of the current world".
According to the agreement, India will invest the money to build the capacity of Chabahar port.
We want to expand connectivity, cooperation in the energy sector and the centuries-old bilateral relationship, said Modi. "It's not based on fairness and is based only on might is right", said President Rouhani at the public lecture.
The port in the Sistan-Balochistan province on the energy-rich nation's southern coast is easily accessible from India's western coast and is increasingly seen as a counter to Pakistan's Gwadar Port, which is being developed with Chinese investment and is located at distance of around 80 km from Chabahar.More news: Were Jennifer Aniston & Justin Theroux Legally Married?
Karbasian was addressing an interactive meeting with Indian and Iranian business leaders, organised by the Federation of Indian Chambers of Commerce and Industry of India.
Rouhani reached New Delhi on day long visit Friday night, after spending two days in Hyderabad, where he offered Friday prayers, met Muslim elite and visited cultural attractions of the city.
India and Iran kept the focus on Chabahar port project and signed a lease contract for the Shahid Beheshti Port-Phase 1 of Chabahar.
In a warm parting gesture, Iranian President Rouhani gifted an animated version of Kalila Wa Demna and a copy of the Mahabharat in Farsi to PM Modi.
Later, External Affairs Minister Sushma Swaraj also called on the visiting dignitary.More news: FBI offers $10K reward in girl's disappearance
This file photo shows former Indian president APJ Abdul Kalam (3rd-L) and his Iranian counterpart Mohammad Khatami at India's Republic Day parade in 2003.