U.S. President Barack Obama said on Tuesday afternoon that the deadly hybrid storm Sandy was " not yet over," urging Americans to get prepared for longer struggle and help others.

Speaking at the national headquarters of the American Red Cross based in Washington D.C., Obama said Superstorm Sandy's impact is obviously "heartbreaking for the entire nation."

He warned Americans across the affected area that the storm is "not yet over" and still has risks, and people should be prepared for days and possibly weeks.

Obama also praised coordination between state and local authorities and pledged that the federal government would continue to push as hard as possible to provide resources for places like hardest-hit New Jersey.

He also asked people to show their generosity by giving donations to aid work by organizations like Red Cross.

Obama will travel to New Jersey on Wednesday afternoon to inspect the damage caused by Sandy, the White House said in a statement issued Tuesday afternoon.

"Tomorrow afternoon, the president will travel to New Jersey where he will join Governor (Chris) Christie in viewing the storm damage, talking with citizens who are recovering from the storm and thanking first responders who put their lives at risk to protect their communities," the statement said.

Heading into the final week before Election Day on Nov.6, the White House announced on Tuesday Obama has canceled his Wednesday' s campaign events for straight three days in order to focus on the rescue and response efforts for deadly and devastating superstorm Sandy.

Sandy, which made landfall in the U.S. state of New Jersey early Monday evening and combined with winter storms to become a hybrid storm, has impacted 15 states. According to local media reports, at least 29 people were killed in eight states, including 15 in New York and three in New Jersey, two of the hardest-hit regions.