Iran and the United States held a fifth round of nuclear negotiations on Friday in Rome, Italy, with enrichment as a key issue.

Iranian Foreign Minister Seyed Abbas Araghchi stressed earlier on Friday that there will be no nuclear deal if the US wants to end Iranian uranium enrichment — a signal that Teheran will not relinquish its right to peaceful nuclear development.

In a live interview with Iranian state-run IRIB TV on Thursday, Araghchi said: "Fundamental differences still exist between us. The US side does not believe in uranium enrichment in Iran. If this is their objective, there would be no agreement," Xinhua News Agency reported.

"However, if they seek that Iran does not move toward nuclear weapons, this can be achieved. We do not seek nuclear weapons," he added.

Steven Witkoff, US special envoy to the Middle East, talked about the Iran nuclear issue with ABC News last week: "We cannot allow even 1 percent of an enrichment capability". Araghchi reiterated that the Iranian nuclear program is entirely peaceful, as repeatedly confirmed by various reports of the International Atomic Energy Agency, or IAEA.

Rafael Grossi, chief of the IAEA, already made it very clear in April this year that Iran does not possess any nuclear weapon.

In a letter sent on Thursday to UN Secretary-General Antonio Guterres, UN Council President Evangelos C. Sekeris and Rafael Grossi, Araghchi formally notified the UN and the IAEA that Iran will take "special measures" to defend its people, its interest and its nuclear facilities, with details to be disclosed to the UN and the IAEA later, IRAN reported.

Iran's Supreme Leader Ali Khamenei has derided demands from the US to halt its peaceful nuclear growth. "Saying things like 'We will not allow Iran to enrich uranium' is nonsense. No one in Iran is waiting for others' permission," said Khamenei in a speech reported by the country's semi-official Mehr News Agency on Tuesday.

Agencies contributed to this story.