pbs.org — Activities at Natanz were suspended in 2004 following an agreement negotiated by Britain, France and Germany. But Iran restarted its uranium enrichment at the FEP after President Mahmoud Ahmadinejad's election in 2005. By mid-2010, Iran had 3,936 P-1 centrifuges producing low enriched uranium up to 3.5 percent, and a total of 8,428 P-1 centrifuges installed.