Washington, May 27 (IANS): US President Barack Obama Sunday called on Americans to help rebuild the tornado-ravaged Oklahoma City area during a visit to places hit by a deadly twister last week.

The president caught a glimpse of the damage from the air before Air Force One landed in Oklahoma Sunday, Xinhua reported.

Obama began touring some of the hardest-hit areas and met officials and residents in the Oklahoma City suburb of Moore, a town of some 41,000 people.

The tornado, classified as an EF-5 or the strongest storm on Earth with winds of speed of more than 300 km per hour, killed 24 people and injured 377 others.

As many as 12,000 homes were damaged. Official statistics estimated the damage caused by the tornado at $2 billion.

Speaking in front of the wreckage of the Plaza Towers Elementary School, where seven children died in the tornado, Obama urged Americans to help in the storm relief and reconstruction efforts.

"It's going to take a long time for this community to rebuild, so I want to urge every American to step up," the president said.

He asked the public to donate via the American Red Cross website.

"This area has known more than its share of heartbreak, but the people pride themselves on the 'Oklahoma standard'," Obama said.

"Oklahomans have inspired us with their love and their courage and their fellowship."

Obama vowed that the nation would help.

"This is a strong community with strong character," he said.

"There's no doubt they' re gonna bounce back. But, they need help, as anyone would need help."

Oklahoma Governor Mary Fallin said the state needs quick action from the Federal Emergency Management Agency (FEMA) to help Moore town.

In recent days, Obama has offered prayers for the people of Oklahoma from the White House.

"While the road ahead will be long, their country will be with them every single step of the way," he said.

Earlier, the White House said that FEMA has already provided $57 million in rebates and incentives to help build about 12,000 storm shelters in Oklahoma.