US

AP Exclusive: Secret document lifts Iran nuke constraints

  • FILE -- In this July 14, 2015 file photo, young Iranian men cheer and show victory signs while holding a picture of Foreign Minister Mohammad Javad Zarif, reading "Zarif is Mosaddegh of our time," comparing Zarif to Mohammad Mosaddegh, Iran's legendary prime minister during the 1950s who nationalized the country's oil industry, in Tehran, Iran. A document obtained by The Associated Press Monday, July 18, 2016, says key nuclear restrictions on Iran will ease in a little more than a decade, halving the time Tehran would need to build a bomb if it chose to do so. The document says that 11 to 13 years into the 15-year agreement, Iran can replace the 5,060 inefficient centrifuges it now uses to enrich uranium with up to 3,500 advanced machines. (AP Photo/Ebrahim Noroozi, File)

    FILE -- In this July 14, 2015 file photo, young Iranian men cheer and show victory signs while holding a picture of Foreign Minister Mohammad Javad Zarif, reading "Zarif is Mosaddegh of our time," comparing Zarif to Mohammad Mosaddegh, Iran's legendary prime minister during the 1950s who nationalized the country's oil industry, in Tehran, Iran. A document obtained by The Associated Press Monday, July 18, 2016, says key nuclear restrictions on Iran will ease in a little more than a decade, halving the time Tehran would need to build a bomb if it chose to do so. The document says that 11 to 13 years into the 15-year agreement, Iran can replace the 5,060 inefficient centrifuges it now uses to enrich uranium with up to 3,500 advanced machines. (AP Photo/Ebrahim Noroozi, File)  (The Associated Press)

  • FILE -- This Oct. 27, 2004 file photo, shows the interior of the Arak heavy water production facility in Arak, 360 kms southwest of Tehran, Iran. A document obtained by The Associated Press Monday, July 18, 2016, says key nuclear restrictions on Iran will ease in a little more than a decade, halving the time Tehran would need to build a bomb if it chose to do so. The document says that 11 to 13 years into the 15-year agreement, Iran can replace the 5,060 inefficient centrifuges it now uses to enrich uranium with up to 3,500 advanced machines. (AP Photo/Fars News Agancy, File)

    FILE -- This Oct. 27, 2004 file photo, shows the interior of the Arak heavy water production facility in Arak, 360 kms southwest of Tehran, Iran. A document obtained by The Associated Press Monday, July 18, 2016, says key nuclear restrictions on Iran will ease in a little more than a decade, halving the time Tehran would need to build a bomb if it chose to do so. The document says that 11 to 13 years into the 15-year agreement, Iran can replace the 5,060 inefficient centrifuges it now uses to enrich uranium with up to 3,500 advanced machines. (AP Photo/Fars News Agancy, File)  (The Associated Press)

  • FILE - In this July 2, 2015 file photo, Iran's President Hassan Rouhani, right, shakes hands with the Director General of the International Atomic Energy Agency, IAEA, Yukiya Amano, as they pose for photos at the start of their meeting in Tehran, Iran. A document obtained by The Associated Press Monday, July 18, 2016, says key nuclear restrictions on Iran will ease in a little more than a decade, halving the time Tehran would need to build a bomb if it chose to do so. The document says that 11 to 13 years into the 15-year agreement, Iran can replace the 5,060 inefficient centrifuges it now uses to enrich uranium with up to 3,500 advanced machines. (AP Photo/Ebrahim Noroozi, File)

    FILE - In this July 2, 2015 file photo, Iran's President Hassan Rouhani, right, shakes hands with the Director General of the International Atomic Energy Agency, IAEA, Yukiya Amano, as they pose for photos at the start of their meeting in Tehran, Iran. A document obtained by The Associated Press Monday, July 18, 2016, says key nuclear restrictions on Iran will ease in a little more than a decade, halving the time Tehran would need to build a bomb if it chose to do so. The document says that 11 to 13 years into the 15-year agreement, Iran can replace the 5,060 inefficient centrifuges it now uses to enrich uranium with up to 3,500 advanced machines. (AP Photo/Ebrahim Noroozi, File)  (The Associated Press)

A document obtained by The Associated Press shows that key restrictions on Iran's nuclear program will ease in slightly more than a decade, halving the time Tehran would need to build a bomb.

The document is the only secret text linked to last year's agreement between Iran and six foreign powers. It says that after a period between 11 to 13 years, Iran can replace its 5,060 inefficient centrifuges with up to 3,500 advanced machines.

Since those are five times as efficient, the time Iran would need to make a weapon would drop from a year to six months.

Iran says its enrichment is peaceful, but the program could be used for nuclear warheads.

Two diplomats providing the information Monday demanded anonymity because they weren't authorized to do so.