Iran and India have signed an agreement to develop the Iranian port of Chabahar.
Speaking in Tehran on May 23, Indian Prime Minister Narendra Modi described the deal as "an important milestone" that will help boost economic growth in the region.
Modi said India would invest $500 million to develop Chabahar in southeast Iran, adding that his country would build and operate the port.
Iranian President Hassan Rohani said the project could "turn into a very big symbol of cooperation" between the two countries.
Afghan President Ashraf Ghani also flew in to Tehran on May 23 for the signing of a trilateral agreement between Tehran, New Delhi, and Kabul to turn Chabahar into a transit hub between the three countries, bypassing Pakistan.
Modi and Rohani also witnessed the signing of cooperation agreements in the fields of aerospace, biotechnology, nanotechnology, and counterterrorism.