Trump lashed out at San Juan, Puerto Rico's mayor on Saturday morning. Getty Images/Pool

President Donald Trump kicked off the weekend by attacking the mayor of San Juan, who recently begged the federal government to send more help to Puerto Rico in the wake of Hurricane Maria.

"I am begging, begging anyone who can hear us to save us from dying," Carmen Yulin Cruz, San Juan's mayor, said Friday morning. "If anybody out there is listening to us, we are dying, and you are killing us with the inefficiency."

Cruz also implied that Puerto Rico had received far more help from corporations and private entities than from the federal government.

"This is what we got last night: four pallets of water, three pallets of meals and 12 pallets of infant food — which I gave them to the people of Comerio, where people are drinking off a creek," Cruz said. "So I am done being polite. I am done being politically correct. I am mad as hell. So I am asking the members of the press, to send a mayday call all over the world. We are dying here."

Trump responded shortly after, criticizing Cruz's leadership ability in a Saturday morning tweetstorm. He made the remarks while staying at his golf club in Bedminster, New Jersey.

"The Mayor of San Juan, who was very complimentary only a few days ago, has now been told by the Democrats that you must be nasty to Trump," Trump said on Twitter. "...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."

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's response to Cruz's appeals for help earned immediate and sustained criticism, particularly from Democrats and celebrities, who blasted the president for attacking the mayor of a hurricane-ravaged city from the confines of his golf course.