The Trump administration on Tuesday denied a request to waive shipping restrictions to help get fuel and supplies to storm-ravaged Puerto Rico, saying it would do nothing to address the island's main impediment to shipping: damaged ports.

The Jones Act limits shipping between coasts to U.S. flagged vessels. However, in the wake of brutal storms, the government has occasionally issued temporary waivers to allow the use of cheaper, tax-free or more readily available foreign-flagged ships.

The Department of Homeland Security, which waived the act after hurricanes Harvey and Irma, did not agree an exemption would help this time.