Iran is preparing a counter-proposal after rejecting the U.S. nuclear deal, prompting President Trump to caution that "time is running out."

Even as the United States and Iran grapple with each other’s nuclear red lines, the simple fact of engagement underscores a pragmatic turn for Tehran regarding President Donald Trump.

President Trump claimed Monday that the U.S. won't allow Iran to enrich uranium under a potential nuclear deal. Why it matters: Trump's claim contradicts the proposal his envoy Steve Witkoff made to Iran on Saturday,