As part of the agreement, state-owned precious metals and gems repository Gokhran purchased a first batch of diamonds from Alrosa this month.
The European Union added Alrosa, Russia's biggest diamond producer, to its sanctions list in January as part of the punitive measures it has imposed on Moscow over the conflict in Ukraine.
Due to sanctions, the ministry has decided not to disclose the details of the deal, but said it plans to sell the diamonds bought by Gokhran depending on market conditions.
Reuters reported the deal on Wednesday citing a source familiar with the matter.
(Reporting by Daria Korsunskaya; Writing by Maxim Rodionov; Editing by Kirsten Donovan)
