The letter, so far signed by over 190 legislators, demands the government to get “stronger guarantees” from the US in the Vienna talks on the removal of sanctions.

It also calls for respect for Iran’s previously-announced redlines and securing the national interests in the Vienna talks.

The Iranian lawmakers in a statement in February had called on the administration of President Rayeesi to adhere to Iran’s red lines as the talks inched forward in Vienna.

They said the US government and its European allies had shown that they were not bound by any agreement over the past few years, so Iran was obliged to learn from the experience and set clear red lines.

The red lines, according to the lawmakers, include guarantees by the United States and the three European signatories of the JCPOA that they would not abandon a potential agreement again and seek recourse to “the snapback mechanism”, which would reinstate the UN Security Council’s sanctions against Iran. They also asserted that all sanctions imposed under “false excuses” had to be removed.

Iranian officials have repeatedly said the US should remove all illegal sanctions against the Islamic Republic in a verifiable manner and guarantee that a new US administration would not breach the JCPOA once again.

Former US president Donald Trump unilaterally left the JCPOA in May 2018 and re-imposed the anti-Iran sanctions that the deal had lifted. He also placed additional sanctions on Iran under other pretexts not related to the nuclear case as part of his “maximum pressure” campaign.

In May 2019, following a year of strategic patience, Iran decided to let go of some of the restrictions on its nuclear energy program, resorting to its legal rights under the JCPOA, which grants a party the right to suspend its contractual commitments in case of non-compliance by the other side.

The Biden administration says it is willing to compensate for Trump’s mistake and rejoin the deal, but it has retained the sanctions as leverage.

Last month, the talks in Vienna, aimed at resurrecting the JCPOA, were paused for an undetermined period of time but later reports suggested that they were in final stages.