The president is making the announcement to curb the use of the rapid-fire devices during a ceremony recognizing bravery by the nation's public safety officers.
Trump is responding days after the shooting deaths of 17 people at a Florida high school. He's pointing to the need to propose regulations to ban the device that was used in the October shooting deaths of 58 people in Las Vegas.
White House officials say the president will be meeting with students, teachers and state and local officials to discuss ways of providing more school safety and address gun violence. Past efforts to address gun violence in Congress have failed.