Majid Takht Ravanchi, Iran’s ambassador to the United Nations, pictured here in 2015 at a news conference in Mexico City. In an exclusive interview with NPR, Ravanchi said flaring tensions between Washington and Tehran have made diplomatic talks hostile.

Majid Takht Ravanchi, Iran’s ambassador to the United Nations, pictured here in 2015 at a news conference in Mexico City. In an exclusive interview with NPR, Ravanchi said flaring tensions between Washington and Tehran have made diplomatic talks hostile.