A staff person removes the Iranian flag from the stage after a group picture with representatives of the United States, Iran, China, Russia, Britain, Germany, France and the European Union during the Iran nuclear talks in July 2015 in Vienna. Carlos Barria/Pool/AFP via Getty Images hide caption
The International Atomic Energy Agency has been responsible for policing the Iran deal. It has sealed some equipment, preventing its use, and installed cameras and other electronic monitoring. AFP/IRNA/AFP via Getty Images hide caption
A pumpjack operates in the desert oil fields in southern Bahrain on April 22, 2020. Bahrain and other members of the OPEC+ alliance decided Thursday to keep output largely unchanged as they hope to push crude prices even higher after a recent rally. Mazen Mahdi/AFP via Getty Images hide caption
Director General of the International Atomic Energy Agency (IAEA) Rafael Mariano Grossi meets over the weekend with Iranian Foreign Minister Mohammad Javad Zarif. Fatemeh Bahrami/Anadolu Agency via Getty Images hide caption
State Dept. Spokesman Ned Price, seen on Monday, says the Biden administration is willing to talk with Iranian and European officials about the nuclear deal. Kevin Lamarque/AP hide caption
People hold posters showing the portrait of Maj. Gen. Qassem Soleimani at a protest outside the U.S. Consulate on Jan. 5 in Istanbul, Turkey. Chris McGrath/Getty Images hide caption
The European Union's foreign policy chief, Josep Borrell, talks to reporters Tuesday at the European Parliament in Strasbourg, France. The same day, the U.K., France and Germany announced they were lodging a dispute against Tehran under the Joint Comprehensive Plan of Action, or JCPoA, better known as the Iran nuclear deal. Jean-Francois Badias/AP hide caption
Iranian Foreign Minister Mohammad Javad Zarif arrives to speak at the United Nations on Wednesday. Kena Betancur/AFP/Getty Images hide caption
From left: Iran's Atomic Energy Organization spokesman Behrouz Kamalvandi, government spokesman Ali Rabiei and Deputy Foreign Minister Abbas Araghchi give a joint press conference at the presidential headquarters in the capital Tehran on Sunday. Iran is enriching uranium beyond a 3.67% cap set by the nuclear deal. Hamed Malekpour/AFP/Getty Images hide caption
The Sultan Qaboos Mosque in Salalah, Oman. The country has emerged as a quiet facilitator of dialogue, including between Iran and the U.S. Sam McNeil/AP hide caption
An Iranian security official in protective clothing walks through a uranium conversion facility in 2005. Iran says it is now enriching uranium above the limit set in the 2015 nuclear deal. Vahid Salemi/AP hide caption
A file photo from Jan. 15, 2011, shows Iran's heavy water nuclear facility near Arak. Iran plans to walk back modifications to a nuclear reactor at the site. Hamid Foroutan/AP hide caption
After Iran shot down a U.S. drone, President Trump speculated that "it could have been someone loose and stupid" behind the surface-to-air missile strike. The president spoke about the issue on Thursday as Secretary of State Mike Pompeo (center) and White House national security adviser John Bolton looked on in the Oval Office. Jonathan Ernst/Reuters hide caption
Atomic Energy Organization of Iran spokesman Behrouz Kamalvandi, pictured at a July 2018 news conference in Tehran, said Monday: "We have quadrupled the rate of enrichment and even increased it more recently." Atta Kenare/AFP/Getty Images hide caption
Iranian President Hassan Rouhani says Iran will begin keeping its excess uranium and heavy water, and he set a 60-day deadline for new terms to its nuclear deal before the country will resume higher uranium enrichment. Rouhani is seen here at a cabinet meeting in Tehran on Wednesday. Iranian Presidency Office/AP hide caption