BRUSSELS/ TEHRAN — The EU on Thursday urged Iran to reverse its scale-back of commitments to the nuclear accord struck with world powers after the Islamic Republic announced it was ending curbs on atomic research.

European Commission spokesman Carlos Martin Ruiz de Gordejuela told a media briefing in Brussels that the decision was "inconsistent" with the Joint Comprehensive Plan of Action, under which the accord is implemented.

"And in this context we urge Iran to reverse these steps and refrain from further measures that undermine the nuclear deal," he said.

Meanwhile, Iran said on Thursday that it will announce details on Saturday of its latest scaling back of its commitments under a 2015 nuclear deal in response to sweeping US sanctions.

Atomic energy organization spokesman Behrouz Kamalvandi will hold a news conference to set out the details of Iran's third cut to its nuclear commitments since May, the semi-official ISNA news agency said.

President Hassan Rohani said Wednesday that the new steps included abandoning all limits set by the 2015 deal to Iran's nuclear research and development.

He spoke of "expansions in the field of research and development, centrifuges, different types of new centrifuges, and whatever we need for enrichment," but did not elaborate.

Iran and three European countries — Britain, France and Germany — have been engaged in talks to try to save the nuclear deal that has been unraveling since US President Donald Trump withdrew from it in May last year and unilaterally reimposed sanctions.

Iran has expressed mounting frustration at Europe's failure to offset the effect of renewed US sanctions in return for its continued compliance with the agreement.

It had already hit back twice with countermeasures in response to the US withdrawal from the deal.

On July 1, Iran said it had increased its stockpile of enriched uranium to beyond the 300-kilogram maximum set by the agreement.

A week later, it announced it had exceeded a 3.67-percent cap on the purity of its uranium stocks.

The UN's nuclear watchdog, the International Atomic Energy Agency, said on Aug. 30 that Iran's uranium stockpile stood at about 360 kilograms and that just over 10 percent of it was enriched to 4.5 percent.

Rohani has stressed that the countermeasures Iran has adopted are all readily reversible if the remaining parties to the deal honor their undertakings to provide sanctions relief. — Agencies