Iran tested a new medium-range ballistic missile last month in a breach of two UN Security Council resolutions, U.S. officials have said.
Fox News reported on December 7 that the test was held on November 21 near Chabahar, a port city near Iran's border with Pakistan.
Fox said White House officials were "aware" of reports of the missile test, but had no comment.
All ballistic-missile tests by Iran are banned under a 2010 Security Council resolution that remains valid until a nuclear deal between Iran and six world powers is implemented.
Under that deal, reached on July 14, most sanctions on Iran will be lifted in exchange for curbs on its nuclear program, but Iran is expected to refrain from work on ballistic missiles designed to deliver nuclear weapons for up to eight years.
In October, the United States, Britain, France, and Germany called for the Security Council's Iran sanctions committee to take action over a missile test by Tehran that month that they said violated United Nations sanctions.
So far, no action has been taken by the committee.