German Foreign Minister Heiko Maas speaks during a joint press conference with Turkish Foreign Minister on July 2, 2020 in Berlin. (PHOTO / AFP)

The Iran nuclear deal remains the “best instrument” to resolve the dispute over Tehran’s atomic program and its signatories are ready to welcome back the US under a Joe Biden administration, according to German Foreign Minister Heiko Maas.

President Donald Trump pulled the US out of the 2015 accord and reinstated sanctions on Iran, and Maas said the deal has been in a “downward spiral” since, fueled by pressure from Washington and Iranian breaches of the terms.

President Donald Trump pulled the US out of the 2015 accord and reinstated sanctions on Iran, and German Foreign Minister Heiko Maas said the deal has been in a “downward spiral” since

However, he said a “final window” remains to salvage it. After virtual talks Monday, Maas and his counterparts from France, Britain, China, Russia and Iran -- as well as the European Union’s foreign affairs chief -- issued a statement praising “the prospect of a US return” and underlining “their readiness to take a positive view of this in a joint effort.”

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“Now we have to look forward and the next weeks and months will decide whether the deal can be saved,” Maas told reporters in Berlin. “But it’s about much more than that,” he added. “Behind this is the question of whether a long-term solution to the decades-long dispute about Iran’s nuclear program can be found through negotiation.”

Jake Sullivan, President-elect Biden’s nominee for national security adviser, this month expressed guarded optimism about restoring the nuclear accord, even as Iran has cut the time it would need to enrich uranium to weapons-grade fuel. Iran has denied it aspires to build a bomb, but world powers entered into the 2015 deal expressly to prevent that from happening.

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Sullivan emphasized that any progress toward preserving or even enhancing the deal would depend on international cooperation. He said that Biden’s goal is to get Iran “to come back into compliance” with the agreement, and that once that is accomplished, new negotiations could begin on other issues, including Iran’s involvement in other Middle Eastern countries.