A former Soviet scientist and experts in Pakistan and North Korea have brought Iran to the threshold of nuclear capability, sources told The Washington Post.
The U.N. International Atomic Energy Agency is scheduled to release a report this week on Iran's nuclear efforts.
Former IAEA official David Albright, president of the Institute for Science and International Security, said international pressure may have paused Iran's nuclear efforts in 2003 but the research has since resumed, the newspaper reported Sunday
"After 2003, money was made available for research in areas that sure look like nuclear weapons work but were hidden within civilian institutions," Albright told The Washington Post.
Iran has long maintained its nuclear activities are energy-related.