unite nations u.s. unilateral sanction iran undermine iran nuclear deal russian foreign minister sergei lavrov say thursday use unilateral sanction ... illegitimate undermine collective nature international efforts everyone witness alarm today new new restrictions u.s. iran lavrov tell u.n. general assembly annual gather world leaders threaten implementation joint comprehensive plan action add refer 2015 international accord iran six world power russia say u.s. iran sanction undermine nuclear deal