President Mahmoud Ahmadinejad on Wednesday vowed that Iran would not yield in the crisis over its nuclear drive as world powers awaited a response from Tehran to a proposal aiming to end the standoff. "The Iranian people are steadfast and will not step back an inch against the oppressive powers," Ahmadinejad told a rally in the southwestern province of Kohgelouyeh-Boyerahmad. "The Iranian nation does not value your threats. You are mistaken if you think you can force this nation to back down with sanctions, threats and pressure," Ahmadinejad said.