The district courts of the United States are vested with jurisdiction specifically to enforce, and to prevent and restrain any person from violating, an order or regulation made or issued under this subchapter.

A civil action authorized to be commenced under this section shall be referred to the Attorney General for appropriate action, except that the Secretary shall not be required to refer to the Attorney General a violation of this subchapter if the Secretary believes that the administration and enforcement of this subchapter would be adequately served by providing a suitable written notice or warning to the person committing the violation or by administrative action under subsection (c).