Some members of Congress want the Trump administration to suspend shipping restrictions that would allow more fuel and emergency supplies to reach Puerto Rico.

The Jones Act prohibits foreign-flagged vessels from picking up and delivering fuel between U.S. ports. That act was suspended from Sept. 8 through Sept. 22 to allow shipments to Texas and Florida after Hurricanes Harvey and Irma. Puerto Rico was included under that waiver for petroleum products.

Since that suspension needed Sept. 22, the Trump administration hasn't issued a new one for Puerto Rico since Hurricane Maria struck. That hurricane wiped out the power supply, destroyed cell towers and led to massive fuel shortages on the island that relies on diesel for much of its power.

President Trump, who plans to visit Puerto Rico on Tuesday, said the administration is studying the waiver request, but that shipping interests are opposed.

"Well, we're thinking about that, but we have a lot of shippers and a lot of people that work in the shipping industry that don't want the Jones Act lifted, and we have a lot of ships out there right now," Trump said. "And I will tell you the governor was very generous yesterday with some statements and so was the mayor of San Juan; very, very generous with their statements."

Sen. John McCain, R-Ariz., wrote to the Department of Homeland Security urging a waiver and ultimately "a full repeal of this archaic and burdensome act."

“These emergency waivers have been valuable to speed up recovery efforts in the impacted regions," McCain said. "However, I am very concerned by the department’s decision not to waive the Jones Act for current relief efforts in Puerto Rico, which is facing a worsening humanitarian crisis following Hurricane Maria."

Any request formally goes to Customs and Border Protection and the secretary of Homeland Security.

There was “sufficient capacity” of U.S.-flagged vessels to serve Puerto Rico, Gregory Moore, a spokesman for Customs and Border Protection, said in a statement.

Waiver requests must be in the interest of national defense. The Defense Department, which made a request for Hurricane Harvey, hasn't made a new request for Puerto Rico yet. If another agency or shipping company makes the request, it must also be reviewed by the U.S. Maritime Administration.

The Defense Department said in a statement Wednesday that the sea-based response to the disaster will shift to a land-based approach for a longer-term recovery, led by the Federal Emergency Management Agency and the local government.

“Fuel distribution remains the top FEMA priority,” the statement said. “Multiple DOD elements delivered fuel and continue route-clearance operations.”

Elaine Duke, the acting secretary of Homeland Security, told a Senate panel Wednesday that when she spoke with Puerto Rico's governor at 1 p.m. Tuesday he had no unmet emergency needs. The problem is getting supplies across the island cluttered with debris and landslides, she said.

"First of all, we don't know of fuel shortages on the island of Puerto Rico," Duke told the Homeland Security and Governmental Affairs Committee. "The challenge for us today is getting it distributed."

Charlie Papavizas, a Washington-based maritime lawyer and partner at Winston and Strawn LLP, said Jones Act waivers before 2005 were typically granted for specific vessels, not for general purposes such as a fuel shortage. But more general waivers have been granted since then for hurricanes Katrina, Rita, Sandy and Irma, he said.

“I do not believe there is any precedent at all for waiving the Jones Act for general purposes,” Papavizas said. “There has to be a national defense justification by law for a waiver, and the only economic related national defense justification acceptable to date — since at least 1950 — has been related to regional fuel shortages.”

The U.S. Virgin Islands, which were hit by multiple hurricanes, have a permanent waiver to the Jones Act under the law, but Puerto Rico wasn't included in that provision.

For House members to seek a waiver is unusual, but the department is considering it. A decision was not expected Wednesday, according to a senior administration official, who spoke on background in a conference call with reporters.

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“When Hurricane Maria savaged the Island, many of our deepest fears were realized,” said Rep. Nydia Velázquez, D-N.Y., who is leading the effort to suspect restrictions for Puerto Rico. “With a power grid that already faced serious infrastructure problems, the storm has shut down power for the entirety of Puerto Rico."