United Nations Secretary-General Antonio Guterres has appealed to U.S. President Joe Biden's administration to lift or waive all sanctions on Iran as agreed under the 2015 Iran nuclear deal, officially known as the Joint Comprehensive Plan of Action (JCPOA). 

In a report to the UN Security Council on the implementation of the deal, Guterres also urged the United States to "extend the waivers with regard to the trade in oil with the Islamic Republic of Iran, and fully renew waivers for nuclear non-proliferation projects." 

His appeal to Washington came amid talks to revive the JCPOA, under which Iran accepted curbs on its nuclear program in return for a lifting of many foreign sanctions against it. 

Washington withdrew from the deal in 2018 and reimposed sanctions on Tehran. In response, Iran gradually stopped implementing parts of its JCPOA commitments from May 2019.  

"I appeal to the United States to lift or waive its sanctions outlined in the plan," said Guterres, who also appealed to Iran to return to full implementation of the deal.

Iran has refined uranium up to a purity of roughly 60 percent, far above the deal's limit of 3.67 percent, though it maintains that it seeks only civilian nuclear power and could quickly reverse its moves if Washington rescinded sanctions and returned to the 2015 deal. 

Guterres said: "I continue to believe that a full restoration of the Plan remains the best way to ensure that the nuclear program of the Islamic Republic of Iran remains exclusively peaceful." 

Negotiations have been going on in Vienna since April to iron out steps Iran and the U.S. must take on nuclear activities and sanctions to return to full compliance with the deal.  

Iran's delegation chief Abbas Araqchi said on June 20 that parties to the JCPOA are "closer than ever to an agreement" after the sixth round of talks. U.S. national security adviser Jake Sullivan said there are still disagreements. 

Iranian government spokesman Ali Rabiei said on Tuesday that the current administration is not in a rush to push for the negotiations before the new government takes power in August. 

"If what we have in mind is ensured, there will be no delay, but if it is not, the continuation of the negotiations will be adjourned to the next government," the spokesman for the outgoing Hassan Rouhani administration said. 

China has stressed that in order to resume full compliance with the JCPOA, the U.S. should first lift its unilateral sanctions against Iran, including "long-arm jurisdiction" against third-party entities and individuals. 

(With input from Reuters, Xinhua)