Donald Trump on Saturday attacked San Juan's mayor and other Puerto Rican authorities, scornful of his complaints regarding a slow response to the hurricane that threatens the island's future. "What poor leadership from the mayor of San Juan and others in Puerto Rico who cannot get their workers to help," Trump said in a series of Twitter messages a day after the mayor asked for help to prevent deaths.

Carmen Yulin: 'Killing us inefficiently'

"They want (others) to do everything when it should be an effort of the whole community," wrote Donald Trump.The messages represented an aggressive response to San Juan Mayor 'Carmen Yulin Cruz', who had accused the Trump administration of "killing us inefficiently" after Hurricane Maria.

She begged the president, who has a scheduled trip to the island next Tuesday, to "make sure someone is in charge of saving lives." Trump has repeatedly praised residents of Florida, Louisiana, and Texas, who were also affected by devastating storms, as strong and resilient.

Trump promised maximum help

Donald Trump promised to spare no effort to help Puerto Rico recover from the catastrophic consequences of Maria, and tweeted that the military and rescuers are doing "a wonderful job," although there is no "electricity, roads, telephones, etc."

However, after a week of mounting criticism, Trump’s patience seems to be dwindling. His administration has tried in recent days to counter the view that it failed to grasp the magnitude of the destruction caused by Maria and the urgency it needed.

The administration gave Puerto Rico less attention than it gave to the states hit by Harvey and Irma. After spending days without mentioning the storm-devastated islands, government officials attended some press conferences describing aid efforts and Trump mentioned Puerto Rico at almost every public event.

The life coming back to Puerto Rica

Thousands of Puerto Ricans received more water and food in aid distribution. Telecoms have been re-established on about 30% of the island, almost half of the supermarkets have been reopened for at least a few hours a day, and approximately 60% of the gas stations are running. However, many still have urgent needs, especially water, after the September 20 hurricane.

Trump is expected to hold an hour-long telephone conversation with the administrator of the Federal Emergency Management Agency (FEMA), Brock Long, Puerto Rico's governor Ricardo Rosella, and other local officials.

'Goal is to save lives'

Carmen Cruz refused to enter into the discussion and preferred to ask for united focus around the people who need help. "The goal is one: saving lives. This is the time is to show our 'true colors.' We cannot be distracted by anything else," she tweeted, along with photos of her meeting with residents and rescuers, walking waist-deep in a flooded street and comforting an elderly woman.

Natural disasters sometimes represent rare moments of bipartisan solidarity.

After Hurricane Sandy, which destroyed the East Coast in 2012, New Jersey Republican Governor Chris Christie praised Democratic President Barack Obama for his attention and compassion. Still, the cash-for-recovery fight has become political and controversial, with many Republicans voting against an aid law.