Germany, on Friday, called on Iran to "fully cooperate" with the Vienna-based International Atomic Energy Agency (IAEA) and "answer all open questions" about its nuclear program, Anadolu News Agency reports.
"We support the IAEA's call on Iran. The country must cooperate fully and extensively with the IAEA. Ensure the transparency of its nuclear program and answer all open questions," Foreign Ministry deputy spokeswoman, Andrea Sasse, told a news conference in Berlin.
She also expressed regret that the recent trip of IAEA Director-General, Rafael Grossi, to Tehran yielded no results.
"In fact, there were no tangible results, as Grossi himself said at his press conference. Iran has once again failed to keep its promises," Sasse said.
Grossi said on Wednesday that the UN nuclear watchdog was unable to reach an agreement with Iran in recent talks on its role in monitoring the country's atomic program.
Speaking at a news conference at the IAEA headquarters in Vienna, Grossi said the negotiations in Tehran had been inconclusive.
Grossi, whose remarks came after the quarterly meeting of the agency's board, said that though he had tried to address the constraints placed on inspections in Iran after 23 February, major problems remain on the presence of undeclared nuclear material at specific sites in Iran and the treatment of IAEA staff in the country.
Meanwhile, Sasse refused to speculate on a plan B if the Vienna nuclear talks, set for this Monday, fail.
As negotiations on getting the Iran nuclear deal back on track are set to resume, the Iranian side is hopeful that the talks will lead the US to lift its sanctions against Tehran.
The nuclear accord was signed in 2015 by Iran, the US, China, Russia, France, the UK, Germany and the European Union. Under the agreement, Tehran has committed to limit its nuclear activity to civilian purposes and in return, the world powers agreed to drop their economic sanctions against Iran.
However, the US, under then-President Donald Trump, unilaterally withdrew from the agreement in 2018 and re-imposed tough sanctions on Iran, prompting Tehran to stop complying with the nuclear deal.
Both Tehran and Washington continue to maintain their positions. While Iran wants the removal of all American sanctions and guarantees given by Washington not to abandon the agreement again, the US is calling for Iran to comply with its commitments.
Earlier this month, Ali Bagheri, Iran's Deputy Foreign Minister and chief negotiator in nuclear talks with world powers, visited London, Paris and Berlin to resolve the nuclear standoff.