President Donald Trump came face to face with hurricane-ravaged Puerto Rico on Tuesday after denouncing critics of the federal relief effort as “politically motivated ingrates” who need to step up their own response to the crisis.

Puerto Ricans who have called Washington’s work on the island insufficient “have to give us more help”, he said before leaving Washington.

Air Force One brought the president, first lady Melania Trump and aides to Puerto Rico late on Tuesday morning.

Donald TrumpPresident Donald Trump tosses paper towels into a crowd as he hands out supplies at Calvary Chapel in Guaynabo, Puerto Rico (Evan Vucci/AP)

They were expected to spend more than five hours on the ground, meeting emergency personnel, local officials and some of the 3.4 million people whose lives have been upended by a hurricane that, in the president’s words, left the island US territory “flattened”.

The plane descended over a landscape marked by mangled palm trees, metal debris strewn near homes and patches of stripped trees, yet with less devastation evident than farther from San Juan.

As he headed out to visit the island earlier, Mr Trump praised the federal response, telling reporters at the White House that “it’s now acknowledged what a great job we’ve done”.

He added that at “a local level, they have to give us more help”.

Mr Trump added: “In Texas and in Florida, we get an A-plus.

“And I’ll tell you what, I think we’ve done just as good in Puerto Rico, and it’s actually a much tougher situation.”

The trip will be Mr Trump’s fourth areas battered by storms during an unusually violent hurricane season that has also seen parts of Texas, Florida, Louisiana and the US Virgin Islands inundated by floodwaters and hit by high winds.

Nearly two weeks after Maria hit Puerto Rico, 95% of electricity customers remain without power, including some hospitals.

Much of the countryside is still struggling to access such basic necessities as food, fresh water and cash.

Mr Trump’s visit follows a weekend in which he aggressively hit back against critics, including San Juan mayor Carmen Yulin Cruz.

Mr Trump responded angrily on Twitter, deriding the “poor leadership ability by the mayor of San Juan, and others in Puerto Rico, who are not able to get their workers to help”.

“They want everything to be done for them when it should be a community effort,” he added, scoffing at “politically motivated ingrates” who had criticised the federal work, and insisting “tremendous progress” was being made.

Ms Cruz had accused the administration of “killing us with the inefficiency” and begged the president to “make sure somebody is in charge that is up to the task of saving lives”.

Mr Trump said on Tuesday that Ms Cruz has “come back a long way” in her criticism, noting the recent moderation in her remarks.

He added: “The first responders, the military, Fema, they have done an incredible job in Puerto Rico. And whether it’s her or anybody else, they’re all starting to say it.”

Ms Cruz told the White House she would attend the president’s first event: a briefing on hurricane relief efforts at the airport hangar, said White House spokeswoman Sarah Huckabee Sanders.

Mr Trump and his wife were to attend briefings and meet with Governor Ricardo Rossello, as well as the governor of the US Virgin Islands.

They were also meeting Navy and Marine Corps personnel on the flight deck of the USS Kearsarge.

As Mr Trump toured the island he pledged an all-out effort to help Puerto Rico.

He said Puerto Rico suffered a relatively low death toll from Hurricane Maria compared with “a real catastrophe like Katrina,” which killed more than a thousand people in 2005.

While “every death is a horror,” Mr Trump drew a distinction between “a real catastrophe like Katrina” and “what happened here” in Puerto Rico, where at least 16 people died.