In an interview with the IRIB on Saturday, Salehi said the project pertains to stable isotopes and a series of research centers at Fordow.
The first phase of the project is going to be inaugurated within the next days, while the official opening will be celebrated on April 9, 2018, he added.
Located in the central province of Qom, Fordow is buried deep underground to protect it against any enemy attacks.
In late 2011, the plant at Fordow began producing uranium enriched to 20 percent fissile purity.
But since January 2014, Iran has been producing lower-level uranium with an enrichment level of up to 5 percent in Fordow and in another enrichment plant in Natanz, under an agreement with the Group 5+1 (Russia, China, the US, Britain, France and Germany).
Salehi announced earlier this week that Iran is capable of restarting the process of enriching uranium to a purity level of 20 percent in just five days, backing up comments by the president that Iran can swiftly regain advanced nuclear capabilities.
Whenever it wants to, Iran can begin 20 percent uranium enrichment at the Fordow nuclear site in five days at the most, Ali Akbar Salehi said on Tuesday.