U.S. President Donald Trump lifted restrictions on foreign shipping on Thursday to help get fuel and supplies to Puerto Rico as the U.S. territory reels from the devastation of Hurricane Maria, the White House said.

Trump, at the request of Puerto Rican Governor Ricardo Rossello, "has authorized the Jones Act be waived for Puerto Rico. It will go into effect immediately," White House spokeswoman Sarah Sanders said in a Twitter post.

The Jones Act limits shipping between U.S. ports to U.S. owned-and-operated vessels.

Puerto Rico's government had sought a waiver of the law to ensure as many supplies as possible, including badly needed fuel, reach the island of 3.4 million people quickly.

Rossello retweeted Sanders' announcement with a "Thank you @POTUS" - referring to Trump's official Twitter handle.

Maria struck Puerto Rico on Sept. 20, knocking out power to the entire island, causing widespread flooding and major damage to homes and infrastructure.

Even as federal emergency management authorities and the U.S. military have stepped up relief efforts, many residents have voiced exasperation at the prolonged lack of electricity, reliable supplies of drinking water and other essentials.

Rossello has strongly praised Trump's response, defending the Republican administration against complaints of being slow to act and showing too little concern.

Critics have said Puerto Rico is not getting the same response as it would if it were a U.S. state, even though its residents are U.S. citizens.

The U.S. government has periodically lifted the Jones Act for a temporary period following violent storms, including after hurricanes Harvey and Irma, which hit Texas and Florida in late August and earlier this month.