President Joe Biden told survivors of a horrific blaze in Hawaii the government would not abandon them as he toured the scene of the worst wildfire the US has seen in over a century.

The 80-year-old donned the mantle of comforter-in-chief as he saw for himself the devastation wreaked on Lahaina by a fire that killed at least 114 people as it levelled the historic town.

"I know the feeling that many people in this town, this community (have); that hollow feeling you have in your chest like you're being sucked into a black hole," he said as he stood by the blackened skeleton of a historic banyan tree.

"We're with you for as long as it takes, I promise you, by making sure your voices are heard.

"We're gonna rebuild the way that the people of Maui want to build. The fire cannot reach the roots. That's Maui. That's America."

Biden is fighting a rearguard action against criticism his government was too slow to respond to the disaster, with locals angry at what some of them see as a plodding official response.

Former president Donald Trump said it was "disgraceful" that his successor had not been in Hawaii more quickly, though the White House has said Biden delayed his trip so as not to distract officials and rescuers working on the ground.

Residents have also lashed out at Maui officials who they say should have sounded an alarm system as the fire erupted.
Biden and First Lady Jill Biden walked through the ravaged remains of Lahaina with Hawaii's governor Josh Green and his wife, nearly two weeks after ferocious, wind-whipped blazes sent residents jumping into the ocean to escape the flames.

After a helicopter tour of the damage, Biden is due to announce further relief funding and the appointment of a federal response coordinator.

Biden, who travelled from Nevada where he was vacationing, said in a statement that "I know nothing can replace the loss of life. I will do everything in my power to help Maui recover and rebuild from this tragedy."

- Agonizingly slow -

FEMA Administrator Deanne Criswell, defending the government's response, said Biden's one-day visit should underscore his commitment to ensuring Hawaii's recovery.

She said more than 1,000 federal responders were now in Hawaii -- and added that none of them would have to be moved to the US Southwest, which is contending with the effects of Tropical Storm Hilary.

Maui residents say the process of recovering lost loved ones -- and identifying bodies -- has been agonizingly slow, criticizing the government for a sluggish response.

As a result, "a warm welcome may not be assured for Biden in some circles on Maui," the Honolulu Star-Advertiser newspaper concluded.

While search teams have covered 85 percent of the search zone, the remaining 15 percent could take weeks, Governor Josh Green said on CBS's "Face the Nation." The fire's extreme heat meant it might be impossible to recover some remains.

Criswell acknowledged that the process could be slow but said the federal government had sent experts from the FBI, the Defense Department and the Department of Health and Human Services to help with the painstaking identification process.

Presidential visits to major disaster zones, while viewed as almost politically mandatory, can carry risks.

When President George W. Bush traveled to Louisiana in 2005 to witness the historic devastation of Hurricane Katrina, critics seized on pictures of him looking out the window of Air Force One while flying over New Orleans to say his arms-length visit lacked empathy.

And when then-president Donald Trump casually tossed rolls of paper towels into a crowd in hurricane-ravaged Puerto Rico in 2017, critics called his gesture cavalier and insensitive.