The Un ited States and Iran clashed at the Un ited Nations on Monday (Apr 27) over Tehran's nuclear programme and its selection to be one of dozens of vice presidents at a month-long conference to review the nuclear Non-Proliferation Treaty (NPT). The 11th conference to review implementation of the NPT, which came into force in 1970, began on Monday at the Un ited Nations in New York. Different groups nominated 34 conference vice presidents, and the conference chair, Vietnam's UN ambassador Do