Representatives from Iran, Russia, and China began a trilateral meeting behind closed doors in Moscow on Tuesday, with no press access, according to Iranian state media.
The meeting, which started on Tuesday afternoon, was previously announced by Iranian Foreign Ministry Spokesman Esmail Baghaei.
Baghaei said on Monday that the discussions would be held at an expert level and would focus on the Iranian nuclear program, the Joint Comprehensive Plan of Action (JCPOA), and UN Security Council Resolution 2231.
According to the spokesman, the Iranian delegation consists of mid-level representatives and legal experts from the Ministry of Foreign Affairs.
The specific agenda and expected duration of the trilateral meeting were not disclosed.