The Iranian president arrived in the country earlier in the day at the invitation of his Sri Lankan counterpart Ranil Wickremesinghe after a trip to Pakistan.
The Uma Oya hydropower complex, a megaproject financed by Iran, was initially launched in 2013 and was scheduled to be inaugurated in 2015 but was delayed due to US-led sanctions.
The project, valued at about $514 million, will add 290 GWh to Sri Lanka’s national grid and supply water to 6,000 hectares of farmland and drinking water to thousands of families near the capital Colombo.
In Sri Lanka, Raisi is scheduled to meet high-ranking officials and sign a number of cooperation documents.