"The goal of the talks is to find a way for Iran to fully return to its obligations under the nuclear deal. What we are now hearing from Tehran does not positively contribute to this," Maas told reporters, adding that the talks proceed "not easily, though constructively."
In 2015, Iran signed the JCPOA with the P5+1 group of countries. The agreement required Iran to scale back its nuclear program and downgrade its uranium reserves in exchange for sanctions relief. In 2018, the United States withdrew from the JCPOA and began imposing sanctions on Iran, the latter being in violation of the nuclear agreement.
Iran retaliated by gradually abandoning its own commitments under the deal a year later.
Late last week, a senior US State Department official said that Iran's demand to lift all the sanctions is a non-starter for Washington. According to the spokesperson, the negotiations in Vienna may reach an impasse if Tehran keeps insisting on its position.