The head of Iran’s Atomic Energy Organization, Ali Akbar Salehi, told lawmakers on 28 July 2019 that Iran will restart activities at the Arak heavy-water nuclear reactor. Heavy water is used in reactors to produce plutonium. Plutonium is a fuel used in nuclear warheads.
Iran’s meeting with the European countries:
Regarding this US Sanctions on Tehran, a meeting was conducted between Iranian officials and the UK, France, and Germany, in Vienna. In the meeting, Iran persuaded the European states to provided more effective relief from US sanctions.
The move is after the US’s withdrawal from the 2015 nuclear deal and the introduction of sanctions on Tehran, Iran stopped complying with some commitments in the 2015 nuclear deal.