European Union foreign policy chief Federica Mogherini and Iranian Foreign Minister Mohammad Javad Zarif made the announcement during a joint press conference in Vienna on Saturday.
Mogherini read out a statement in English which was subsequently read out by Zarif in Persian.
"As Iran has fulfilled its commitments, today, multilateral and national economic and financial sanctions related to Iran's nuclear program are lifted in accordance," read the statement. "All sides remain firmly convinced that this historic deal is both strong and fair, and that it meets the requirements of all."
"This achievement clearly demonstrates that with political will, perseverance, and through multilateral diplomacy, we can solve the most difficult issues and find practical solutions that are effectively implemented," it added.
"UN sanctions related to Iran's nuclear programme are lifted. United Nations Security Council resolution 2231 (2015), which endorsed the JCPOA, will from now onwards, together with the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), be the sole international legal framework related to Iran's nuclear activities, terminating provisions of resolutions 1696 (2006), 1737 (2007), 1747 (2007), 1803 (2008), 1835 (2008), 1929 (2010) and 2224 (2015)."
US Secretary of State John Kerry, also present in Vienna, confirmed the IAEA’s report, saying that “The US sanctions-related commitments... are now in effect."
Kerry said the United States would “immediately” remove sanctions imposed on Tehran, “expanding the horizon of opportunity for the Iranian people.”
Iranian President Hassan Rouhani responded to the announcement by hailing the Iranian nation in a tweet for the “glorious victory.”
Earlier on Saturday, IAEA Director General Yukiya Amano announced that Iran had taken the “necessary preparatory steps to start the implementation of the Joint Comprehensive Plan of Action (JCPOA).”
Iranian Ambassador to the IAEA Reza Najafi announced that Amano would be traveling to Iran to meet Rouhani, Head of the Atomic Energy Organization of Iran (AEOI) Ali Akbar Salehi, and other officials on Sunday.
Meanwhile, US President Barack Obama signed an executive order for the removal of sanctions on Iran, the White House announced.
Iran and the five permanent members of the UN Security Council – Britain, China, France, Russia and the United States – plus Germany finalized the JCPOA in Vienna, on July 14, 2015.
Under the JCPOA, limits are put on Iran’s nuclear activities in exchange for the removal of sanctions against the Islamic Republic.