U.S. Secretary of State Marco Rubio said there were "good signs" a deal could be reached with Iran, though he rejected Tehran tolling ships transiting the Strait of Hormuz, the Financial Times reported May 21. Meanwhile, the Israel Defense Forces remain on high alert for the potential resumption of major fighting.

U.S. House Republicans called off a vote on a resolution to curb U.S. military actions against Iran after a similar effort passed in the Senate. During the Iran war, the United States has used around 200 THAAD interceptors (around half of the Pentagon's total inventory) in defense of Israel, in addition to 100 SM-3 and SM-6 interceptors. By contrast, Israel has reportedly launched fewer than 190 Arrow and David's Sling interceptors.