A nuclear weapon uses a fissile material to cause a nuclear chain reaction. The most commonly used materials were uranium 235 (U-235) and plutonium 239 (Pu-239). Uranium 233 (U-233) and plutonium from the reactor were both used.    The required amount of uranium or plutonium depends on the sophistication of the design, a simple construction requiring about 15 kg of uranium or 6 kg of plutonium and requiring a sophisticated design as little as 9 kg of uranium or 2 kg of plutonium.  Plutonium is almost non-existent in nature and natural uranium is about 99.3% uranium 238 (U-238) and 0.7% U-235. To make a weapon, you have to either enrich uranium or produce plutonium. Uranium enrichment is also often necessary for nuclear energy. This is why uranium enrichment is a dual-use technology, a technology that “can be used for both civilian and military purposes.”  Key strategies for preventing nuclear proliferation include limiting the number of uranium enrichment facilities operated and controlling the export of nuclear technology and fissile material.   October 31, 2019: The U.S. State Department grants a 90-day extension of the lifting of sanctions for certain nuclear cooperation projects in Iran, but it remains unclear what waivers will be renewed. In July 2019, the Trump administration waived sanctions to allow China, Russia and European JCPOA members to continue certain undelased activities under the nuclear deal, including the conversion of Iran`s Arak reactor and Fordov enrichment plant, the transfer of 20% enriched uranium fuel for the Tehran research reactor, and the removal of used fuel from the Buhers reactor.
The July 2019 waiver declarations expired in October. December 3, 2007: The United States releases an unclassified summary of a new report on Iran`s nuclear program. The NIE says the secret service found “with great confidence” that Iran had stopped its nuclear weapons program in the fall of 2003 and noted with some confidence that the program had not resumed since mid-2007. The report defines Iran`s nuclear program as a “design and weapon work,” as well as a clandestine processing and enrichment of uranium. The NIE also stated that Iran was technically capable of producing enough highly enriched uranium for a nuclear weapon between 2010 and 2015. The Iranian revolution took place in 1979 and Iran`s nuclear program, which had developed a certain starting capacity, was shaken when “a large part of Iran`s nuclear talent fled the country as a result of the revolution”.  In addition, Ayatollah Ruhollah Khomeini was initially opposed to nuclear technology and Iran waged a costly war with Iraq from 1980 to 1988.  On the first day of implementation, Washington imposed new sanctions on 11 companies and individuals for supplying Iran`s missile program.    According to Kerry, a debt of $1.7 billion was to be paid to Tehran with interest. But some Iranian financial institutions, including Ansar Bank, Bank Saderat, Bank Saderat PLC and Mehr Bank, remained on the SDN list and a series of U.S.
sanctions on Iran, including existing sanctions on terrorism, human rights and ballistic missiles.  Mr. Hook met with representatives of the Government of Bahrain and jointly issued a joint statement expressing a firm commitment to “fighting Iranian aggression” and “asking the UN Security Council to extend the arms embargo imposed on Iran before its expiration”. On July 18, Obama dedicated his weekly radio address to the agreement, saying, “This agreement will make America and the world safer and safer,” refuting “a lot of overheated and often dishonest arguments about it”;  Obama said, “As commander-in-chief, I make no apologies for keeping this country safe and secure through hard diplomatic work on the mild warstorm.”  On July 23, In the White House Cabinet Room, O