"Iran & Russia are determined to deal with unilateral & illegal approaches to resolve global crises,” Zarif wrote on his Twitter account on Tuesday, according to a report by IRNA.
"From joint statement with FM Lavrov in Moscow today, where we reaffirmed commitment to int'l law as US & cronies attack foundation of int'l relations at IAEA & Security Council," he added.
Earlier in the day, speaking at a joint press conference with his Russian counterpart Sergei Lavrov in Moscow, Zarif had said Iran would not let the International Atomic Energy Agency (IAEA) to become a tool for ending Iran nuclear deal known as the Joint Comprehensive Plan of Action (JCPOA).
Iran has always behaved with full transparency with the IAEA, he said arguing that 15 reports of the IAEA have indicated that Iran has always been committed.
"We will not let Iran be subject to investigation the documents of which are based on spying claims," he noted.
Iran will give a suitable response if the IAEA wants to take advantage of illogical ways, Zarif reiterated.
Iranian and Russian foreign ministers in a joint statement on Tuesday underlined opposing the unilateralism of the United States and some of its Western allies in the international arena.