"Everyone knows that, at this point, it will be necessary to wait for the new Iranian government," Rafael Grossi said in an interview with Italian daily La Repubblica, in reply to a question about what stage negotiations on the deal were at, US News reported.
Grossi, director-general of the International Atomic Energy Agency (IAEA), appeared to be referring to Iran's presidential elections, due on Friday.
Iran's new president is expected to name his cabinet by mid-August. The term of current President Hassan Rouhani ends on Aug. 3, a government spokesman said.
The sixth round of talks to revive the deal resumed in Vienna on Saturday between Iran and world powers.
The IAEA does not take any direct part in the negotiations but has been called on to verify them and continue inspections in the country.
"The discussions that have been going on for weeks have dealt with very complex and delicate technical questions, but what is needed is the political will of the parties," Grossi said.
Since April, representatives from Iran and the P4+1 group of countries have been holding talks in Vienna aimed at revitalizing the JCPOA and bringing the US back to compliance. The US has sent a delegation to Vienna but it is not attending the JCPOA Joint Commission talks directly as Washington is no longer a party to the deal. It has, however, held separate talks with the other parties to the JCPOA.
Under former president Donald Trump, the US left the JCPOA in 2018 and returned the sanctions that had been lifted against Tehran as part of the agreement. US President Joe Biden has said Washington is willing to return to the pact if Tehran first suspends its countermeasures taken in response to US violations and reimposition of sanctions.
Iran says the onus is on the US to revive the deal as it was Washington, not Tehran, that left the internationally recognized accord in defiance of global criticism.
RHM/PR