German Foreign Minister Heiko Maas said on Monday that time is of the essence in the Vienna talks to resurrect the 2015 Iran nuclear agreement, adding that the talks were lengthy but conducted in a positive atmosphere.

Last week, US officials returned to Vienna for a fourth round of indirect talks with Iran on how to re-establish conformity with the agreement, which was abandoned by former US President Donald Trump in 2018, causing Iran to begin breaching its terms a year later.

“The negotiations are difficult and time-consuming, but both parties are working together constructively,” Maas said on the sidelines of a meeting with his European Union counterparts in Brussels.

“However, the clock is ticking. We want the Iran nuclear deal to be fully restored because it is the only way to ensure that Iran will not be able to acquire nuclear weapons “Added he.