Twenty students and six adult victims were fatally shot by a gunman -- who later killed himself -- at the Sandy Hook Elementary School in the town of Newtown in the US state of Connecticut on Friday.
One person was also injured in the incident.
"The majority of those who died today were children, beautiful little kids between the ages of five and ten years old," Obama said on Friday. "They had their entire lives ahead of them, birthdays, graduations, weddings, kids of their own."
"We are going to have to come together and take meaningful action to prevent more tragedies like this regardless of the politics," Obama said.