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President Donald Trump.
"Results of recovery efforts will speak much louder than complaints by San Juan Mayor. Doing everything we can to help great people of PR!" he said on Twitter.
Trump's tweets came after he faced mounting criticism of his jabs at the mayor of San Juan, Carmen Yulîn Cruz. Cruz had told media on Friday that if Trump does not ramp up relief efforts, Puerto Rico could see "something close to a genocide."
"My Administration, Governor @RicardoRossello, and many others are working together to help the people of Puerto Rico in every way … #FakeNews critics are working overtime, but we're getting great marks from the people that truly matter!" Trump said on Saturday.
He continued: "We must all be united in offering assistance to everyone suffering in Puerto Rico and elsewhere in the wake of this terrible disaster."
Trump - who is spending the weekend at his golf course in Bedminster, New Jersey - took to Twitter to fire back, saying that Cruz, "who was very complimentary only a few days ago, has now been told by the Democrats that you must be nasty to Trump."
He continued: "Such poor leadership ability by the Mayor of San Juan, and others in Puerto Rico, who are not able to get their workers to help."
Reuters/Alvin Baez
Puerto Ricans are still grappling with power outages and a severe gas shortage.
Trump then continued tweeting into the afternoon, praising other Puerto Rican officials, including Governor Ricardo Rossello and Congresswoman Jenniffer Gonzalez-Colon.
Trump has faced backlash in recent days for his slow response to the ongoing crisis in Puerto Rico, and has been criticized for appearing less attentive to the crisis in Puerto Rico than he was to Texas and Florida after those states were ravaged by hurricanes. It's been compared to the bungled federal response to Hurricane Katrina in 2005 under President George W. Bush.
Hurricane Maria left many of Puerto Rico's 3.4 million US citizens without shelter, water, power, and other basic necessities.
"They want everything to be done for them when it should be a community effort. 10,000 Federal workers now on Island doing a fantastic job," Trump said on Saturday. "The military and first responders, despite no electric, roads, phones etc., have done an amazing job. Puerto Rico was totally destroyed."
Trump, along with First Lady Melania Trump, is set to visit the island on Tuesday.
Jeremy Berke contributed reporting.