Russian Foreign Minister Sergey Lavrov warned of a full-scale armed conflict in the Middle East on Friday, Anadolu Agency reports.
Speaking at a BRICS foreign ministers meeting in Rio de Janeiro, Lavrov said the US steps against Iran had led to a harsh escalation in the Persian Gulf region.
"The situation has reached a dangerous point fraught with the risk of a large-scale military clash. This cannot be allowed to happen," he said.
Tensions have been running high between the US and Iran since Washington unilaterally withdrew from a landmark 2015 nuclear deal last year.
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The agreement was an outcome of protracted negotiations between Tehran and the five permanent members of the UN Security Council, plus Germany and the EU.
The US has since launched a diplomatic and economic campaign, to force Iran to renegotiate the deal.
If the US manages to break the Iran nuclear deal, it will strike a severe blow at the regime of non-proliferation of nuclear weapons, he added.
Lavrov called on Iran to exercise restrain and the UK, France and Germany to meet their obligations under the Iran nuclear deal.