In this U.S. Navy handout, sailors aboard the amphibious assault ship USS Kearsarge (LHD 3) move move pallets of supplies on the flight deck during a replenishment-at-sea with the fast combat support ship USNS Supply (T-AOE 6) for continuing operations in Puerto Rico on September 28, 2017. Kearsarge is assisting with relief efforts in the aftermath of Hurricane Maria.

President Donald Trump issued a plea for unity on Saturday in response to the unfolding humanitarian crisis in Puerto Rico, yet critics heaped new scorn and outrage on the president after he lambasted the mayor of San Juan for her "poor leadership."

In a series of early morning posts on Twitter, Trump lashed out at Mayor Carmen Yulin Cruz, who a day earlier said officials were "killing us with the inefficiencies" in the effort to recover from Hurricane Maria.

Although she did not name Trump directly, the federal government's assistance to the island has been widely criticized, particularly after Maria laid siege to Puerto Rico's already fraying infrastructure.

Still, Trump hammered Cruz for her "poor leadership ability...and others in Puerto Rico, who are not able to get their workers to help." Trump, who said he would visit the ravaged island this week, has vowed to pull out all the stops to help the commonwealth recover, and congratulated the efforts of the military and Puerto Rico's first responders.

Later in the day, the president made an appeal for cooperation while imploring the public to dismiss what he called "fake news" that painted the government's efforts in a negative light.

Critics, however, continued to assail Trump's initial response, and rallied around Cruz and the effort to alleviate the disaster, which has left the island reeling.

We must all be united in offering assistance to everyone suffering in Puerto Rico and elsewhere in the wake of this terrible disaster.

To the people of Puerto Rico: Do not believe the #FakeNews! #PRStrong