"It is necessary to somehow find a way out of the situation since there is quite a real prospect of full destruction of the deal in foreseeable future", Ulyanov said at a Moscow-Vienna video conference on the results of the 63rd General Conference of the International Atomic Energy Agency.
The diplomat warned that Tehran is most likely to proceed to the fourth stage of reducing its obligations under the accord in November.
"The third step was made in September, and it included installing centrifuges and conducting research works. There are high chances, and we can expect that the fourth step will be made in early November, and so on, until Iran gets what it expects, namely, restoring the balance between nuclear and economical commitments within the nuclear deal", Ulyanov said.
He also criticised steps of the US administration, noting that restrictions imposed on top-ranked Iranian politicians are meaningless, as they are reducing the chances for settling the crisis around the nuclear deal.
The statement follows a new round of sanctions on the Iranian Central Bank and sovereign wealth funds, imposed by Washington last week. Commenting on the tensions, Iranian President Hassan Rouhani said during a speech at the UN General Assembly on Wednesday that Tehran would only enter negotiations with the American side if it returns to the JCPOA and stops imposing sanctions against the Islamic Republic.
The ties between the US and Iran deteriorated in May 2018, when President Donald Trump announced US withdrawal from the nuclear deal. Precisely one year later, Tehran suspended part of its obligations under the JCPOA and promised to reduce other limitations every 60 days unless other signatories abide the deal and shield Iran from the American hostile economic policies.