"To honour the victims of Monday's horrific shooting at the Washington Navy Yard, the president will attend a memorial service on Sunday," White House Press Secretary Jay Carney told reporters.
Details of the memorial service would be announced later.
"I think the President will want to mourn the loss of these innocent victims and share in the nation's pain in the aftermath of another senseless mass shooting," Carney said.
Twelve people, including Indian-American defense contractor Vishnu Pandit, were killed by a lone gunman who was shot down after the brazen shooting rampage at the high-security Navy Yard on Monday.