Ali Akbar Velayati, the foreign policy adviser to Iranian Supreme Leader Ayatollah Ali Khamenei, has outlined a number of steps Iran can take to strengthen its nuclear program in the face of the US exit from the three-year-old deal in which Iran reduced its nuclear activities in exchange for sanctions relief.

Velayati's first recommendation was to make operational UF6 (uranium hexafluoride), which is a compound used in uranium enrichment. Asghar Zarean, the deputy head of the Atomic Energy Organization of Iran, had previously discussed testing the use of UF6 into more modern IR8 centrifuge machines under the supervision of the International Atomic Energy Agency (IAEA). UF6 is a feedstock for centrifuges. After uranium is mined and processed into yellowcake, it is turned into gas and injected into centrifuges in the form of UF6.

Velayati also discussed the possibility producing nuclear propulsion systems, in order to build nuclear-powered ships and submarines. Velayati said a nuclear-powered submarine has the advantage of staying under water for two years. As Donald Trump had previously threatened to break the nuclear deal between Iran and five permanent members of the United Nations Security Council plus Germany, Iran had previously addressed the possibility of building a nuclear-powered submarine. While the construction of the submarine would require proposals to be sent to the IAEA to still fall within the framework of the nuclear deal, which Iran and Europe are trying to keep alive, the discussion of the subject seemed to be a response and an escalation to Trump’s threats.

The use of carbon fiber composites for more advanced IR6 and IR8 centrifuges was another recommendation by Velayati. He said using the more advanced centrifuges would bring Iran closer to the 190,000 SWU (separative work units) enrichment capacity Khamenei had previously outlined as the country’s goal.