50 U.S. Code § 206 - Suspension of commercial intercourse with part of State in insurrection
Whenever any part of a State not declared to be in insurrection is under the control of insurgents, or is in dangerous proximity to places under their control, all commercial intercourse therein and therewith shall be subject to the prohibitions and conditions of section 205 of this title for such time and to such extent as shall become necessary to protect the public interests, and be directed by the Secretary of the Treasury, with the approval of the President.
Source(R.S. § 5302.)
R.S. § 5302 derived from act July 2, 1864, ch. 225, § 5,13 Stat. 376.