Image caption Benjamin Netanyahu said people in Iran understood the cost of their government's policies. Israel's prime minister has warned the people of Iran that the nuclear deal being negotiated by their country and world powers is very bad for them. Specifically, the world powers want to curtail Iran's ability to enrich uranium, which can be used to make reactor fuel but also nuclear weapons. 2  Disagreement centres on how to limit Iran's development and use of centrifuges that enrich uranium.