Lawmakers ruled out the possibility of renegotiating the 2015 nuclear agreement, as demanded by the Republican US administration, saying it would be against international law.
"According to international law, final international agreements are not renegotiable," Yahya Kamalipour, an MP, told ICANA on Sunday.
When campaigning for the White House, US President Donald Trump railed against the historic pact, seen as a foreign policy legacy of his democratic predecessor, Barack Obama.
He branded it as "a disaster" and "the worst deal ever negotiated" and once even vowed to tear it up if he became president, although he later backtracked on that threat, conceding that it would not be that easy to dismantle a deal enshrined in a UN resolution.
Trump promised to alter the terms of the accord instead.
The nuclear accord was concluded in July 2015 between Iran and the US and its five other partners, which took effect six months later to end sanctions in return for Tehran scaling down its nuclear activities.
Those partners, namely France, Britain, China, Russia and Germany, have refused to go along with Trump's idea of revising the deal, officially referred to as the Joint Comprehensive Plan of Action.
The Trump administration, which admitted Iran is complying with the terms of the accord, has until May 19 to extend the sanctions relief.
However, it said it has launched a full review of the action plan.
"Iran and P5+1 reached the agreement after lengthy negotiations and all parties took on commitments," Kamalipour said.
He said Iran would not enter discussions with the US over the revision of the JCPOA terms and it would agree to do so if the talks are only aimed at facilitating the pact's implementation.
Jalal Mirzaei, another member of parliament, also told ICANA that reopening nuclear talks would amount to derailing the agreement, but he also stressed the need for discussions to clear up ambiguities in the deal.
"The Islamic Republic would come to the negotiating table only to discuss the enforcement of the pact and clarify ambiguities," he said.
