A delegation of Iranian nuclear scientists and procurement agents traveled to Moscow in August 2024 to visit Russian companies that produce dual-use technologies, according to documents reviewed by FT. The delegation was led by Ali Kalvand, the director of Tehran-based consulting firm DamavandTec, and its members included scientists and businessmen linked to Iran's Organisation of Defensive Innovation and Research (SPND). The delegation visited two companies owned by a Russian nuclear scientist and vacuum technology expert that produce klystrons and electron accelerators, which have applications in nuclear weapons testing. Kalvand had earlier written to a Russian nuclear isotope supplier to request radioactive isotope samples including tritium, which has applications in nuclear implosion testing and boosting the yield of nuclear warheads.