NEW YORK, 6 April, 2021, (TON): The United States expects indirect talks with Iran that begin on Tuesday about both sides resuming compliance with the 2015 Iran nuclear deal to be "difficult" and does not foresee any early breakthrough. 

Iran and the United States said on Friday they would hold indirect talks in Vienna Tuesday (today) as part of a wider effort to revive the nuclear deal between Tehran and global powers, formally called the Joint Comprehensive Plan of Action (JCPOA). 

Tehran has ruled out face-to-face bilateral discussions. 

U.S. State Department spokesman Ned Price said on Monday that, "We don't underestimate the scale of the challenges ahead."   

"These are early days. We don't anticipate an early or immediate breakthrough as these discussions, we fully expect, will be difficult," he said.  

US Special Envoy for Iran Rob Malley, a veteran of the Clinton and Obama administrations, will lead the US delegation to the talks, he added. 

The Biden administration has maintained the sanctions on Iran it inherited from the Trump administration, saying it wants both sides to resume complying with the JCPOA but that this requires negotiations.   

"Our goal at these talks … is to set the stage for that mutual return to compliance," Price said.   

Iran has laid down a tough line in advance, with its Foreign Ministry saying on Saturday that it wants the United States to lift all sanctions and rejects any "step-by-step" easing of restrictions.   

In 2015, Iran agreed a long-term deal on its nuclear programme with a group of world powers known as the P5+1 - the US, UK, France, China, Russia and Germany. 

It came after years of tension over Iran's alleged efforts to develop a nuclear weapon. Iran insisted that its nuclear programme was entirely peaceful, but the international community did not believe that. 

European officials expected to act as intermediaries between the U.S. and Iran. Indirect talks are to be held to revive the 2015 pact under which economic sanctions on Iran were eased in return for curbs on Iran's nuclear program to make it harder to develop a nuclear weapon.