President Barack Obama has marked the anniversary of the massacre at Sandy Hook elementary school with a moment of silence at the White House.

Before pausing to remember the Connecticut school tragedy a year ago Saturday, the president and first lady Michelle Obama lit 26 votive candles set up on a table in the Map Room _ one candle for each of the 20 children and six staff members who were killed.

In his weekly radio address released hours earlier, Obama said the nation hasn't done enough to make its communities safer by keeping dangerous people from getting guns and healing troubled minds.

Gun restrictions backed by the president in response to the shooting faced stiff opposition from the National Rifle Association and ultimately stalled in the Democratic-controlled Senate.