Iran's ambassador to the UN, Mohammad Khazaee, criticized the dual-track policy as "contradictory" and said sanctions undermine rather than encourage diplomacy.
"For some in the U.S., pressure has become an end in itself," he said in a speech in New York Feb. 20. "As long as the U.S. leaders choose to base their policy towards Iran on 'my way or the highway,' they should rest assured that Iran would not compromise on its basic rights under pressure or threat."
Iran's Supreme Leader Ayatollah Ali Khamenei complained in a Feb. 16 speech that world powers only want the Islamic Republic to bend to their will. "What's the point of such negotiations?" he said. "This won't lead anywhere."
Sanctions proponents, such as Mark Dubowitz, the executive director of the Washington-based Foundation for Defense of Democracies, say that even more pressure is needed.
It's not surprising Iran is in no mood for compromise, because the country is "closing in on an undetectable nuclear breakout" point at which it could produce enough weapons-grade fuel before being detected by UN inspectors or Western intelligence services, Dubowitz said in an interview.