Qatari mediators in Iran are working on a deal in which both Iran and the US will make a series of concessions over a five-day period, including Iran resuming shipping in the Strait of Hormuz and the US lifting its naval blockade of Iranian ports. The main obstacles to reaching this deal are related to when each side will have to implement its concessions, as well as the fact that Qatari mediators are insisting on concessions regarding Iran's nuclear program, which Iranian negotiators are rejecting.