Vienna, 3 December 2021 (dpa/MIA) - Iran has taken a destructive stance in the recently reinitiated nuclear negotiations, according to high-ranking European diplomats. "Iran is breaking with almost all the difficult compromises that were agreed as the result of several months of hard negotiations," German, French and British negotiators said on Friday. The window of opportunity for a diplomatic solution in the nuclear dispute is getting smaller and smaller, they warned. After five days of talks in Vienna, the delegations returned to their countries and are to meet again next week in the Austrian capital. The negotiations are about restricting Iran's nuclear programme again and lifting US sanctions against the Islamic Republic. The aim is to salvage the 2015 nuclear agreement, which aims to prevent Iran from developing nuclear weapons. When talks were put on hold for five months in June, some elements of a possible return to the deal had already been worked out. "After thorough and careful consideration, we are disappointed and concerned by the changes proposed by Iran to the text negotiated over the last six rounds of the Vienna talks," the European diplomats said. Washington pulled out of the nuclear deal in 2018 under then president Donald Trump and imposed tough economic sanctions. Tehran then overstepped agreed limits on its nuclear programme and began producing near-weapons-grade uranium. At the Vienna talks, the three EU states, together with Russia and China, are mediating between Iran and the United States.