The Iranian team is led by Deputy Foreign Minister for Political Affairs Ali Bagheri Kani.
They arrived in the Austrian capital Vienna earlier on Wednesday.
Before talks with the Chinese delegation, Bagheri Kani met Austrian Deputy Foreign Minister Peter Launsky-Tieffentha and the European Union’s Coordinator of the JCPOA revival talks, Enrique Mora.
More negotiations are set to take place between the Iranian team and other parties within different formats.
The JCPOA revival talks are resumed after they were paused for three months over what Iran calls the US failure to make a political decision to return to the deal and fulfill its commitments.
The US withdrew from the JCPOA in May 2018, reinstating sanctions on Iran.
The Islamic Republic says the sanctions should be fully removed in a verifiable manner.
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