The campaigns' decision follows similar actions taken in 2004 and 2008, when both presidential nominees suspended campaign activities for the day to honor the people lost in the terror attacks, The New York Times reported Thursday.
The group MyGoodDeed, which pushes to have Sept. 11 declared a national day of remembrance, had called for a pause in campaigning.
In 2008, Obama and his opponent, Sen. John McCain, R-Ariz., appeared together at the World Trade Center attack site.
Putin thinks Obama would save him if he were drowning
Chipotle plans first price increase in 3 years