WASHINGTON – President Donald Trump promised a group of Republican lawmakers Wednesday he would not suspend shipping restrictions on natural gas, which would have allowed foreign tankers to transport fuel and energy supplies to Puerto Rico and the Northeast.

“The president gave his word,” said Sen. Bill Cassidy, R-La.

Trump had considered waiving the requirements of the Jones Act, a nearly century-old federal law that dictates only U.S.-flagged vessels can transport fuel between U.S. coasts.

Puerto Rico Gov. Ricardo Rossello requested a 10-year waiver from the law so more fuel and supplies can reach the island, which is still recovering from devastating effects of Hurricane Maria. Some energy leaders also have called for broader changes to the law.

Lifting the law’s requirements, if only temporarily, would allow foreign tankers to move liquefied natural gas (LNG) to Puerto Rico and help facilitate shipments to the Northeast, where there aren’t enough pipelines to supply the region with the fuel.

But lawmakers from states that are home to ports or shipbuilding interests opposed waiving the requirements, arguing that such a move would threaten national security and American jobs.

“Our maritime industry is part of the lifeblood of Louisiana and the Gulf Coast economy,” said Sen. John Kennedy, R-La. “It would be foolish to push aside those jobs in favor of foreign-made and foreign-crewed ships.”

Cassidy, Kennedy and lawmakers from Alaska and Mississippi met with Trump and other administration officials at the White House on Wednesday to argue that lifting the requirements would be a mistake.

Trump assured the group he would oppose any changes or waivers to the law, Cassidy said.

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The Jones Act, which went into effect in 1920, requires that all vessels moving cargo between U.S. ports be built and owned in the United States and operate with U.S. crews. The purpose of the law was to protect the country’s ability to build and maintain a fleet of ships for the national defense and to respond to natural disasters.

The Jones Act has been suspended in the past in response to natural disasters, but only for short periods.

The Trump administration suspended the law’s requirements for two weeks in 2017 to allow shipments to Texas and Florida after Hurricanes Harvey and Irma. Puerto Rico was included under that waiver for petroleum products.

Trump also ordered a 10-day suspension of the requirements for Puerto Rico after Hurricane Maria 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.

When that suspension expired, the Department of Homeland Security said an additional waiver wasn't needed.

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Some energy leaders are encouraging the administration to lift the Jones Act 's requirements altogether, arguing that the law is protectionist and increases fuel costs for U.S. consumers.

"The Jones Act has become an obstacle to using U.S.-produced LNG to meet domestic energy needs,” said Thomas Pyle, president of the American Energy Alliance.

Issuing a waiver for LNG vessels would help circumvent actions by New York Gov. Andrew Cuomo, who has blocked pipelines that would serve several northeastern states and “would deliver much-needed resources to the Northeast,” Pyle said.

The U.S. shipping fleet doesn’t have any vessels that comply with the requirements of the Jones Act, which forces U.S. companies to import the fuel from overseas and at higher prices.

But Democratic and Republican leaders of the House Committee on Transportation and Infrastructure sent a letter in February to the Department of Homeland Security, arguing that such waivers should be restricted to rare cases where it is necessary for national defense.

“It is our belief that no valid national defense rationale exists to support this waiver request,” wrote the committee’s chairman, Rep. Peter DeFazio, D-Ore., and the top panel’s top Republican, Rep. Sam Graves of Missouri.

The letter also was signed by Reps. Sean Patrick Maloney, D-N.Y., and Bob Gibbs, R-Ohio.

In Wednesday's meeting, Kennedy said he argued that lifting the requirements would devastate Louisiana, where thousands of jobs depend on the maritime industry.

"I made the case that the livelihood of Louisiana families is at stake," he said.

Asked how confident he was that Trump would not go forward with the waivers, Cassidy said: "Everyone walked out feeling confident."

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