US President Joe Biden delivers a foreign policy address as Vice President Kamala Harris listens during a visit to the State Department in Washington, US, Feb 4, 2021. [Photo/Agencies] WASHINGTON - US President Joe Biden said the United States would not lift sanctions against Iran unless Tehran stops enriching uranium, according to an interview broadcasted on Sunday. Asked if the United States will lift sanctions first to get Iran back to the negotiating table, Biden said "no" in a Friday interview with CBS News. Biden also gave an affirmative nod when asked if Iran had to stop enriching uranium first. Iran's Foreign Minister Mohammad Javad Zarif said Saturday that Iran is losing patience with the new US administration's "recent signals to retain illegal sanctions" on the Islamic Republic, Press TV reported. US Secretary of State Antony Blinken had noted that Washington would only return to the Joint Comprehensive Plan of Action (JCPOA), also known as the Iran nuclear deal, once Tehran meets its commitments, warning of a long road ahead. The JCPOA was reached in 2015 between Iran and the P5+1 (the five permanent members of the UN Security Council -- the United States, Britain, Russia, France, China, plus Germany) and the European Union. Iran is allowed to enrich uranium within certain limits under the deal. Iran said last month that it was starting to produce 20 percent enriched uranium, as part of Iran's Strategic Action Plan to Counter Sanctions which was approved by the parliament in December 2020. Relations between Washington and Tehran have deteriorated since May 2018 when former President Donald Trump pulled his country out of the Iran nuclear deal and reimposed harsh sanctions against Iran. In response, Tehran has gradually dropped some of its JCPOA commitments since May 2019.