"Such action by the Islamic Republic of Iran would not help preserve the plan, nor secure the tangible economic benefits for the Iranian people.

It is essential that this issue ... be addressed through the mechanism established by the JCPOA," UN spokesman Stephane Dujarric told reporters.

Under the nuclear deal, formally known as the Joint Comprehensive Plan of Action (JCPOA), there is a dispute resolution process that could, within as little as 65 days, end at the UN Security Council with a so-called snapback of UN sanctions on Iran.