Mottaki was due to travel to Moscow for nuclear talks with his Russian counterpart Sergei Lavrov.
It is not known who canceled the visit nor why. It is also unclear whether the meeting will be held at a later stage.
Iran's ISNA news agency reports that Iran's chief nuclear negotiator, Ali Larijani, is due to travel to Moscow on November 9 for talks with senior Russian officials.
(Reuters, AP, AFP, ISNA)
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