US President Barack Obama has heralded the progress New Orleans has made in rebuilding the city since Hurricane Katrina battered the area 10 years ago, but said more needed to be done to overcome poverty and inequality.

On his ninth trip to the city that made worldwide headlines in 2005 after a devastating flood was exacerbated by a slow government response, Mr Obama toured a neighborhood of colourful new houses and a new school and community center.

"Just because the houses are nice doesn't mean our job's done," he told reporters after shaking hands with residents and greeting children from the community.

As a presidential candidate in 2008, Mr Obama sharply criticised Republican President George W Bush for his administration's handling of the aftermath of the storm.

Speaking after almost two terms as president, Mr Obama recalled the storm and its aftermath.

"What started out as a natural disaster became a man-made disaster, a failure of government to look out for its own citizens," he said.

The storm "laid bare a deeper tragedy" of structural inequalities that left "too many people, especially poor people, especially people of colour, without good jobs or affordable healthcare or decent housing," he said.

Mr Obama and other elected officials commemorating the 10th anniversary of the storm said there has been progress.

But the president noted that typical black households still earned less than typical white households in New Orleans and African American men were especially hard hit by unemployment.

With between a year and a year and a half left in his presidency, and a slew of recent racially charged incidents of gun violence and police use of excessive force against minorities, Mr Obama has spent increasing amounts of time publicly addressing racial inequality.

While in New Orleans, Mr Obama had lunch with a group of young black men as part of his "My Brother's Keeper" program, which he has said he plans to continue after leaving office in 2017.

Donna Brazile, a Democratic political strategist and New Orleans native whose father was stranded during flooding from the storm, said the city has begun to address inequality and make greater strides toward recovery.

Levees have been made stronger, homes have been built higher, and jobs are starting to return, Ms Brazile told reporters traveling with Mr Obama.

"We still have a long way to go," she said, estimating that it would take another five or 10 years of hard work.