Iranian officials rejected a recent call for the revision of the 2015 nuclear deal by Rex Tillerson, a candidate for the post of secretary of state under US president-elect, Donald Trump, who will take office next week.
Commenting on Tillerson's remarks, Iran's Deputy Foreign Minister for European and American Affairs Majid Takht-Ravanchi said all parties agree that the accord concluded the nuclear negotiations once and for all.
"As we have repeatedly announced, the JCPOA case will never be reopened and we will not allow this to happen and this is not only the stance of us but that of all members of P5+1," Takht-Ravanchi was quoted as saying by IRNA on Friday.
"Throughout the meeting of Joint Commission in Vienna, other attendees shared our view that we must prevent any problem from hampering the implementation of the action plan and any misuse."
The JCPOA panel's meeting was held earlier this week at the request of Foreign Minister Mohammad Javad Zarif to address Iran's complaint over the extension of anti-Iran sanctions law by the US last month.
Deputy Foreign Minister Morteza Sarmadi noted that the Trump administration would not be able to scrap the landmark agreement unilaterally because five other participants have a say in JCPOA-related decisions.
"The action plan is not [a bilateral deal] between Iran and the United States, so no side can take a unilateral decision," Sarmadi also told reporters.
Morteza Sarmadi
"It is an agreement between Iran and six countries and has been endorsed by the European Union and the United Nations."
Kamal Kharrazi, the head of Iran's Strategic Council on Foreign Relations, noted that an international accord could not be subjected to a revision.
"JCPOA is a written international obligation and cannot be revised," he concluded.
During the campaign trail, Trump railed against the accord clinched between Iran and the outgoing administration of President Barack Obama and five other powers, known as P5+1.
It gave Tehran sanctions relief in return for time-bound curbs on its nuclear work.
Trump called it "a disaster" and "the worst deal ever negotiated" and threatened to pull out of it.
Later he softened his stance and said he would renegotiate it because a deal enshrined in a UN resolution would be too costly to dismantle.
Tillerson echoed that rhetoric during a hearing of the US Senate Foreign Relations Committee on Wednesday, pledging a "full review" of the pact if he got the top diplomat's post.
He said he would increase monitoring and verification systems to ensure Iran does not violate the agreement, formally known as the Joint Comprehensive Plan of Action.
"We need ... to examine our ability to clarify whether Iran is complying," Tillerson told the committee. "That means no nuclear enrichment in Iran, no storing of nuclear materials in Iran."
His call for more rigorous inspections of Iran's nuclear activities came despite reports from the International Atomic Energy Agency that Iran has fully upheld its side of the deal since it was put in place last January.