MOSCOW, Sept. 1 (Xinhua) -- U.S. attempts to re-impose sanctions on Iran are doomed to fail, while Moscow stands ready to mediate between Washington and Tehran, Russian Foreign Minister Sergei Lavrov said Tuesday.

The United States has lost all its rights with Iran by abandoning its obligations under the Joint Comprehensive Plan of Action (JCPOA), known as the Iran nuclear deal, Lavrov said when addressing students of the Moscow State Institute of International Relations.

"The United States wants now to use a rather complex, sophisticated legal instrument, which was laid down in the JCPOA and approved by the United Nations Security Council, to restore the collective sanctions," he said.

"But this mechanism was prepared exclusively for a situation when Iran does not fulfill its obligations, which is not the case," he said.

The top Russian diplomat recalled that the United States did not just say that they were renewing unilateral sanctions, but they aimed to ban all other countries from trading with Iran.

Lavrov said that Russia supports direct dialogue between the United States and Iran, and is ready to help create conditions for that, if both sides are interested.

"It is always better to directly state one's claims and hear a direct answer," he said.