U.S. sanctions key figures in Iran's ballistic missile program

• These "are a reminder that Iran’s development and proliferation of ballistic missiles continues to pose a serious threat to international security," per the Treasury Department.

Details: Mohammad Ali Hosseini, an Iranian procurement agent whose companies helped procure ballistic missile propellant-related materials for the unit of the Islamic Revolutionary Guard Corps that's responsible for the research and development of ballistic missiles, was identified as one of those targeted in sanctions, according to the U.S. Treasury.

• Hosseini's companies also procured materials for Iran's Parchin Chemical Industries (PCI), a part of Iran’s Defense Industries Organization.
• Several of Hosseini's companies were also sanctioned, as was a company that worked as an intermediary for PCI.
• The sanctions dictate that "all property and interests in property of these targets that are in the United States or in the possession or control of U.S. persons must be blocked and reported" to Treasury's Office of Foreign Assets Control.

What they're saying: “This action reinforces the United States’ commitment to preventing the Iranian regime’s development and use of advanced ballistic missiles,” Treasury's undersecretary for terrorism and financial intelligence Brian Nelson said in the statement.

• "We will also work with other partners in the region to hold Iran accountable for its actions, including gross violations of the sovereignty of its neighbors,” Nelson said.

Go deeper: In January, Iran sanctioned more than 50 Americans, including a number of Pentagon officials, over the over the 2020 assassination of Qasem Soleimani.