The European Union is exerting its last effort to revive the Iran nuclear deal and break the stalemate that has been in place for over a month, exacerbated by Washington's unwillingness to meet Iran's demands.

EU foreign policy chief Josep Borrell, speaking to the Financial Times, said he was looking for a "middle way" to end the diplomatic deadlock threatening to bring to naught diplomatic efforts exerted by the EU to bring back into effect the Joint Comprehensive Plan of Action in the Austrian capital through what became known as the Vienna talks.

The Vienna talks between major powers and Iran aim to revive the 2015 nuclear agreement and return the United States to it following its unilateral withdrawal in 2018 under then-President Donald Trump, who accompanied his decision with the imposition of harsh sanctions on Tehran.

The Vienna talks, which also include the United Kingdom, France, Germany, Russia, and China, have been on hold since March 11, with officials saying at the time that the final draft was virtually complete.

The accord going back into effect would see Iran reducing its nuclear activity and the US offering sanction relief in return, lifting the sanctions it had unilaterally imposed and which paralyzed the Iranian economy and even exacerbated the pandemic for the people of Iran.

Borrell said he wanted EU negotiator Enrique Mora to visit Tehran and discuss the issue, though he asserted that Iran was "very much reluctant". He also described the diplomatic push as "the last bullet."

One of the remaining points in the Vienna Talks was the removal of the Islamic Revolution's Guard Corps (IRGC) designation as a terror group. The terror designation means that criminal penalties would be imposed on anyone doing business with any individual or entity connected to the IRGC.

Iran demanded the removal of the IRGC's "terrorist" designation before negotiations proceeded, but bipartisan opposition in Washington and anger from Israelis in West Asia at the prospect of the removal of the designation prevented the US from proceeding through that.

The US administration was considering the removal of the IRGC from its terror blacklist in exchange for a commitment from Iran to "de-escalate" in the region, Axios reported in March.

US officials have said President Biden would not be more lenient nor eliminate the conditions for lifting the designation, while the West blamed Iran for the debacle, making it clear that the talks could come to a close unless Iran offers a pathway through the diplomatic crisis.

The opening for the talks came during an April 23 call between Iranian Foreign Minister Hossein Amir-Abdollahian and Mora. The latter will be trying to persuade Iran to agree to a final accord and kick the issue does the line, diplomats are saying.

Mora visited Tehran in late March to try to resolve the issue over the foreign terrorist designation, though he did not reach any solution.

A senior US official reiterated the words of other diplomats, stressing that Washington did not agree with Iran that the "terrorist" designation should be linked to the talks aimed to spring the accord back to life.

"If it matters to the Iranians that we lift it, we are going to need something that addresses our non-nuclear concerns in exchange," the official said. "If Iran insists the designation has to be lifted and rejects all of the ideas that we put forward, there will be a collapse of the talks."

In light of the war in Ukraine, Borrell said negotiators would not give Iran an ultimatum, with analysts voicing concerns about sparking a separate crisis with Iran while stressing that they want to secure a deal that would enable Tehran to pump out more oil due to the energy crisis sparked by the Western sanctions on Russia.

"We Europeans will be very much beneficiaries from this deal, the situation has changed now. For us it was something . . . 'well we don't need it', now it would be very much interesting for us to have another [crude] supplier," Borrell said. "And the Americans need a diplomatic success."