Countries facing Security Council sanctions “cannot under any circumstances be the subject of one-sided sanctions imposed by one or other government bypassing the Security Council”, Lavrov was quoted as saying by Interfax.

“The position of the United States today does not display understanding of this absolutely clear truth.”

Russia is in talks with the United States and other U.N. Security Council members on a fourth round of sanctions. Moscow has indicated it could support broader sanctions but has stressed they must not harm the Iranian people.

Washington has not publicly warned of unilateral sanctions but has made clear it wants tougher measures than veto-wielding Security Council member Russia is likely to accept.