The nuclear accord, known as the Joint Comprehensive Plan of Action, has been unraveling since the United States pulled out unilaterally in 2018 and reimposed tough sanctions on Iran.
As the remaining parties failed to offset the effects of the sanctions, Iran also moved away from its obligations step by step.
The three European signatories urged Tehran to return to compliance after each phase of its wind-down plan without taking a practical step toward protecting Iran's economic interests.
After the final step of the plan in early January, they even referred the issue to the JCPOA Joint Commission under the Dispute Resolution Mechanism, although they later extended its timeline indefinitely to prevent it from ending up at the United Nations Security Council where global sanctions on Iran would most likely be reinstated.
In an article published on the Project Syndicate online journal, Borrell acknowledged that JCPOA could not survive without guaranteeing Iran's economic interests.
"If we want the Iran nuclear deal to survive, we need to ensure that Iran benefits if it returns to full compliance," he said.
Iran has repeatedly declared that its primary demand is to be able to export its oil and repatriate its revenues, in which case it would immediately reverse all its nuclear measures.
After the US exit, France, Germany and Britain devised a financial mechanism known as INSTEX (Instrument in Support of Trade Exchanges) to facilitate trade between Iran and the EU by circumventing American sanctions.
Around a dozen European countries even welcomed the idea and joined the mechanism, but it has remained on paper even after more than a year of its launch.
"I have to recognize that until now, INSTEX has not been able to produce significant transactions," Borrell had said during his visit to Tehran last week.
The American threats against countries that do business with Iran have made many banks and firms wary of processing transactions with Iran, even in the food and medicinal sectors that are exempt from sanctions.
Switzerland has recently launched a humanitarian channel to ensure that Swiss-based exporters and trading companies in the food, pharmaceutical and medical sectors can sell their products to Iran without landing in the crosshairs of the US Treasury Departmet.
Iranian officials did not express much delight, saying the channel proves that the US pressure campaign had in fact affected the trade of humanitarian goods despite Washington's claims.