While the U.S. has long feared that Iran is using its missile technology to advance its nuclear capabilities, the JCPOA does not expressly prohibit Iran from conducting missile tests. On Friday, the nation’s foreign minister, Mohammad Javad Zarif, defended the actions of the Iranian space program on Twitter, arguing that it does not develop missiles designed to deliver nuclear weapons. “Iran—unlike the U.S.—has complied in good faith with the letter and spirit of JCPOA,” Zarif said, adding that the nation “is not and will not be developing nuclear weapons; so by definition cannot develop anything designed to be capable of delivering them.” The United States’s “rhetoric and actions” on Friday “show[ed] bad faith,” he said.

Indeed, the Trump administration carries a number of reservations about whether Iran has been fully compliant with the JCPOA. Earlier this week, Trump certified that Iran had not violated the deal, but suggested to his aides that he might deny the certification in the future. He later told the Wall Street Journal he would be “surprised” if Iran passed its next review, saying: “If it was up to me, I would have had them noncompliant 180 days ago.” Senior U.S. officials recently told the Associated Press that the Trump administration is pushing for inspections of Iranian military sites, but must first obtain convincing evidence of illicit activity. Trump has also expressed interest in extending the JCPOA—which he once called “the worst deal ever”—beyond its expiration date.

In the meantime, the administration has communicated its concern in the form of sanctions. Earlier this month, the U.S. sanctioned a group of 18 Iranian entities and individuals, including two organizations with alleged ties to the nation’s ballistic-missile program. This week, Congress also approved a sanctions bill targeting Iran, Russia, and North Korea. In order to pass the bill, Trump must agree to a large check on his power that prevents him from loosening or rolling back sanctions without Congress’s approval. The bill now awaits the president’s signature, with the White House offering mixed signals as to whether Trump will sign.

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