President Donald Trump has committed to “full dismantlement,” reiterating on Wednesday that the United States will destroy Iran’s centrifuges “nicely” — through a deal — or “viciously,” through a military strike. But his administration has at other times signaled a softer stance.

Envoys for Iran and the United States have engaged in four rounds of talks. But exactly what a deal would look like remained unclear.

Iran’s president says his country will continue talks over its rapidly advancing nuclear program but will not withdraw from its rights because of U.S. threats