Following the death of Ayotollah Khomeini, the leadership of President Ali Akbar Hashemi Rafsanjani and Supreme Leader Ali Hosseini Khamenei sought to revive Iran's overt nuclear civilian program and expand undeclared nuclear activities during the 1990s. According to a strategic dossier from International Institute for Strategic Studies, Iran turned away from Western suppliers and obtained nuclear assistance from Russia and China in a number of key areas, including uranium mining, milling and conversion, as well as technology for heavy-water research reactors. However, Washington intervened with Moscow and Beijing to prevent Iran from fully acquiring its list of nuclear power and fuel-cycle facilities. The 1990s also saw Iran expand its furtive nuclear research into conversion, enrichment and plutonium separation. "Most importantly, on the basis of additional centrifuge assistance from the A.Q. Khan network, Iran was able to begin the construction of pilot-scale and industrial-scale enrichment facilities at Natanz around 2000." Full exposure of Iran's nuclear activities came in 2002, when an Iranian exiled opposition group, the National Council of Resistance of Iran (NCRI) declared the Natanz project in August of that year. Since that time, international pressure on Iran has remained steady, hampering but not halting the country's nuclear development. Iran remains legally bound to the NPT and states its support for the treaty.