HOUSTON (REUTERS) - US President Donald Trump tried on the role of "comforter-in-chief" on Saturday (Sept 2), playing with children in an evacuation centre and passing out food and supplies to those in need after Hurricane Harvey's assault on Houston.

Trump, dealing with the first natural disaster of his eight-month-old presidency, comforted victims and thanked volunteers and first responders after being criticised earlier in the week for not showing sufficient empathy on his first trip to the storm-battered Texas coast.

Trump, 71, was joined by his wife, Melania, as he passed out food and hugged, kissed and played with children at the "kid zone" in Houston's NRG Centre, a 65,000 sq m facility that was turned in to the city's largest emergency shelter.

Trump appeared relaxed as he posed for photographs with volunteers and chatted with those relocated to the shelter alongside Texas Governor Greg Abbott.

"It has been a wonderful thing," Trump said of his meetings with the children as he helped serve food to evacuees amid shouts of "Thank you, sir."

Trump, who declared Sunday a national day of prayer, then went to a church in nearby Pearland, where he and his wife helped load half a dozen cars with boxes of supplies for victims. He said the volunteer work was "good exercise."

Trump also visited a neighbourhood that had sustained flooding but had dried out to greet residents and praise them for doing "a fantastic job holding it together."

The visit came after a week of historic flooding in the area that killed at least 40 people, displaced more than 1 million and dumped as much as 127cm of rain.

Trump asked Congress late on Friday for an initial US$7.85 billion (S$10.6 billion) for hurricane recovery efforts. The request comes as Washington faces tough budget negotiations.

The trip may have political implications for Trump. According to the Reuters/Ipsos tracking poll, almost 59 per cent of the public disapproves of Trump's performance as president.

His initial trip was contrasted unfavorably with the reaction of former President Barack Obama, who became known as "comforter-in-chief" after mass shootings and the Sandy superstorm that hit New Jersey in 2012.

NOT HAMPERING RELIEF EFFORTS

With floodwaters still present, Trump had stayed clear of the Houston area on his trip to Texas on Tuesday, saying he did not want to hamper rescue efforts. Instead, he met with Cabinet members, state and local leaders and first responders in the state capital Austin and Corpus Christi, where Harvey first hit, focusing on the logistics of the government response.

Trump tweeted that he had seen "first hand the horror & devastation" from Harvey but reporters travelling with him said they saw no damage.

"That was reasonable criticism," said Matt Mackowiak, chairman of the Republican Party in Travis County, Texas, who has praised the Trump administration's handling of the disaster.

On Saturday, some area residents - even one who had voted Democrat - said they believed Trump's visit was a positive.

"It raises the morale," Kevin Jason Hipolito, who identified himself as a Democrat, told reporters at the convention centre. "When he went to Corpus I was like, 'Man he just forgot about us.' This shows a lot of support. It perks up morale."

But it remains a difficult task for Trump, a Republican businessman new to politics, to match expectations set by his predecessors of both parties who were widely considered politically deft at displaying solidarity and commitment to those suffering from disasters both natural and man-made.

"Is he going to help? Can he help?" Devon Harris, 37, a construction worker, said at the convention centre. "I lost my home. My job is gone. My tools are gone. My car is gone. My life is gone. What is Trump going to do?"

Trump was cheered at both the convention centre and a church he visited and appeared to crack a joke, perhaps at his own expense.

While donning gloves to serve food to victims of the disaster in a cafeteria, he commented "my hands are too big," referencing a meme from the presidential campaign in which the size of the candidate's hands were linked to his supposed virility by his opponents, including Republican Marco Rubio.