The European Union foreign policy chief has expressed frustration at delay in Vienna nuclear talks between Iran and world powers.

In a phone call with Iran’s foreign minister Hossein Amir-Abdollahian Friday evening, Josep Borell said the pause in the Vienna negotiations, which broke off March 14, was not constructive and called for fresh talks between Enrique Mora, the senior EU official chairing the process, and Iran’s lead negotiatorAli Bagheri-Kani.

Iran and the United States, which left the Iran nuclear deal in 2018, are reportedly unable to agree over Washington removing Iran’s Revolutionary Guards (IRGC) from its list of ‘foreign terrorist organizations.’ Former US president Donald Trump, who took the US out of the nuclear agreement in 2018 and imposed stringent sanctions, added the IRGC to the list in 2019.

“The Biden administration should have the audacity to rectify the White House’s past mistakes,” Amir-Abdollahian told Borrell in the phone call, according to state-owned Press TV. “There is no doubt about the Iranian government’s will to reach a good, strong, and sustainable agreement…The White House should end its excessive demands and its indecision and walk down the path of realism and resolution.”

The US is only indirectly involved in the Vienna talks over reviving the 2015 agreement, the JCPOA (Joint Comprehensive Plan of Action), but its role is key in deciding which sanctions are incompatible with the agreement and thereby persuading Tehran to reverse steps in its nuclear program taken since 2019 beyond JCPOA limits.

According to Iranian media, Amir-Abdollahian told Borrell that the other participants in the talks − China, France, Germany, Russia, and the United Kingdom − were “ready to finalize agreement” on reviving the JCPOA.

Washington has said its listing of the IRGC is unrelated to the JCPOA and that it will not negotiate the delisting without Iranian concessions "outside the purview of the JCPOA,” a reference to regional security and defense issues.

The Biden administration has come under increasing domestic pressure by most Republicans and some Democrats not to remove the Revolutionary Guard from its terrorist list.

Some argue that the Trump administration designated the IRGC as a terrorist organization to complicate a return to the nuclear deal, but others citing its long list of extraterritorial activities, including support for militant groups say that the designation is well deserved.

A former Iranian diplomat, Ali Jannati, recently claimed that under former President Hassan Rouhani, Iran received a pledge from the Biden administration that to revive the JCPOA it was ready to lift all sanctions introduced by Trump, including the FTO listing of the IRGC and the 2019 executive order allowing sanctioning of individuals linked to the office of Supreme Leader Ali Khamenei. A former Rouhani official, Alireza Moezzi, argued Friday that Jannati could be right, on the grounds that American and European officials had not contradicted him.