ROME -- The fifth round of talks between Iran and the United States started Friday in the Italian capital of Rome with Oman's mediation, according to Iranian media.

The negotiations are led by Iranian Foreign Minister Abbas Araqchi and U.S. special envoy to the Middle East Steve Witkoff, Iran's Tasnim news agency reported, and the talks are indirectly mediated by Omani Foreign Minister Sayyid Badr bin Hamad bin Hamood Albusaidi.

The most recent round of negotiations between the two sides was held in Oman on May 11. According to Italian media reports, tensions have since flared between Iran and the United States over uranium enrichment.

The Trump administration had sought to halt all uranium enrichment by Iran, but Tehran rejected the notion of "zero enrichment" and demanded the lifting of economic sanctions, the report said.

Before arriving in Italy, Araqchi wrote on social media X that "Zero nuclear weapons = we DO have a deal. Zero enrichment = we do NOT have a deal." On Thursday, White House press secretary Karoline Leavitt told reporters that Trump believes talks with Iran are "moving along in the right direction," but still the negotiation could end in either a positive diplomatic solution or a very negative solution for Iran.

Italian Foreign Minister Antonio Tajani told the media that the Italian government "fully supports this mediation effort," but acknowledged that "it is certainly not an easy negotiation."